Method for transmitting and receiving physical uplink control channel in wireless communication system, and device for same

ABSTRACT

According to one embodiment of the present application, a method for transmitting a physical uplink control channel (PUCCH) by a terminal in a wireless communication system comprises a step of receiving setting information associated with a PUCCH, and a step of transmitting the PUCCH on the basis of the setting information. The PUCCH is transmitted from a specific PUCCH resource selected from among overlapped PUCCH resources. The specific PUCCH resource is characterized by being associated with beam failure recovery (BFR).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.17/857,605, filed on Jul. 5, 2022, which is a continuation of U.S.application Ser. No. 17/563,442, filed on Dec. 28, 2021, which is acontinuation under 35 U.S.C § 119(e) of International Application No.PCT/KR2020/008438, filed on Jun. 29, 2020, which claims the benefit ofU.S. Provisional Application No. 62/867,962, filed on Jun. 28, 2019, thecontents of which are all hereby incorporated by reference herein intheir entireties.

TECHNICAL FIELD

The present disclosure relates to a method and apparatus fortransmitting and receiving physical uplink control channels in awireless communication system.

BACKGROUND ART

Mobile communication systems have been developed to guarantee useractivity while providing voice services. Mobile communication systemsare expanding their services from voice only to data. Current soaringdata traffic is depleting resources and users' demand for higher-datarate services is leading to the need for more advanced mobilecommunication systems.

Next-generation mobile communication systems are required to meet, e.g.,handling of explosively increasing data traffic, significant increase inper-user transmission rate, working with a great number of connectingdevices, and support for very low end-to-end latency and high-energyefficiency. To that end, various research efforts are underway forvarious technologies, such as dual connectivity, massive multiple inputmultiple output (MIMO), in-band full duplex, non-orthogonal multipleaccess (NOMA), super wideband support, and device networking.

SUMMARY

The present disclosure proposes a method of transmitting and receivingphysical uplink control channels.

A PRACH-based BFR procedure to which a carrier aggregation (CA) isapplied is limitedly applied to a primary cell (PCell) or aprimary-secondary cell (PSCell). The reason for this is that an ULcarrier may not be present in a secondary cell (SCell) and a contentionbased PRACH cannot be configured.

Accordingly, the present disclosure proposes a method of transmittingand receiving physical uplink control channels for supporting beamfailure recovery of a secondary cell (SCell).

Technical objects to be achieved by the present disclosure are notlimited to the aforementioned technical objects, and other technicalobjects not described above may be evidently understood by a personhaving ordinary knowledge in the art to which the present disclosurepertains from the following detailed description of the presentdisclosure.

A method of transmitting, by a user equipment, a physical uplink controlchannel (PUCCH) in a wireless communication system according to anembodiment of the present disclosure includes receiving configurationinformation related to a physical uplink control channel (PUCCH) andtransmitting the PUCCH based on the configuration information.

The PUCCH is transmitted in a PUCCH resource related to a schedulingrequest (SR).

Based on the PUCCH resource related to the SR being overlapped PUCCHresources, the PUCCH is transmitted in a specific PUCCH resourcedetermined among the overlapped PUCCH resources. The specific PUCCHresource is related to beam failure recovery (BFR).

The beam failure recovery (BFR) may be related to a beam failure of atleast one secondary cell (SCell).

The specific PUCCH resource may be based on a PUCCH format 0 or a PUCCHformat 1.

The method may further include receiving downlink control information(DCI) scheduling a physical uplink shared channel (PUSCH) related to thePUCCH.

The method may further include transmitting the PUSCH based on the DCI.

The PUSCH may be related to a medium access control-control element(MAC-CE) including information related to the beam failure.

The MAC-CE may include information related to at least one of 1) atleast one secondary cell (SCell) or 2) a new beam.

The information related to the new beam may include at least one of i)whether the new beam is present or ii) an ID of a reference signalrelated to the new beam.

The PUCCH related to the beam failure recovery (BFR) may be transmittedbased on a parameter related to the scheduling request (SR).

The parameter related to the scheduling request (SR) may be related toat least one of a timer related to the transmission of the SR or amaximum transmission number of the SR.

A user equipment transmitting a physical uplink control channel (PUCCH)in a wireless communication system according to another embodiment ofthe present disclosure includes one or more transceivers, one or moreprocessors controlling the one or more transceivers, and one or morememories operately coupled to the one or more processors and storinginstructions performing operations when the transmission of a physicaluplink control channel (PUCCH) is executed by the one or moreprocessors.

The operations include receiving configuration information related to aphysical uplink control channel (PUCCH), and transmitting the PUCCHbased on the configuration information. The PUCCH is transmitted in aPUCCH resource related to a scheduling request (SR).

Based on the PUCCH resource related to the SR being overlapped PUCCHresources, the PUCCH is transmitted in a specific PUCCH resourcedetermined among the overlapped PUCCH resources. The specific PUCCHresource is related to beam failure recovery (BFR).

The beam failure recovery (BFR) may be related to a beam failure of atleast one secondary cell (SCell).

The PUCCH related to the beam failure recovery (BFR) may be transmittedbased on a parameter related to the scheduling request (SR).

An apparatus according to still another embodiment of the presentdisclosure includes one or more memories and one or more processorsfunctionally connected to the one or more memories.

The one or more processors are configured to enable the apparatus toreceive configuration information related to a physical uplink controlchannel (PUCCH) and to transmit the PUCCH based on the configurationinformation. The PUCCH is transmitted in a PUCCH resource related to ascheduling request (SR).

Based on the PUCCH resource related to the SR being overlapped PUCCHresources, the PUCCH is transmitted in a specific PUCCH resourcedetermined among the overlapped PUCCH resources. The specific PUCCHresource is related to beam failure recovery (BFR).

One or more non-transitory computer-readable media according to stillanother embodiment of the present disclosure store one or moreinstructions.

One or more instructions executable by one or more processors areconfigured to enable a user equipment to receive configurationinformation related to a physical uplink control channel (PUCCH) and totransmit the PUCCH based on the configuration information. The PUCCH istransmitted in a PUCCH resource related to a scheduling request (SR).

Based on the PUCCH resource related to the SR being overlapped PUCCHresources, the PUCCH is transmitted in a specific PUCCH resourcedetermined among the overlapped PUCCH resources. The specific PUCCHresource is related to beam failure recovery (BFR).

According to an embodiment of the present disclosure, a physical uplinkcontrol channel (PUCCH) is transmitted in a PUCCH resource related to ascheduling request (SR). Based on the PUCCH resource related to the SRbeing overlapped PUCCH resources, the PUCCH is transmitted in a specificPUCCH resource determined among the overlapped PUCCH resources. Thespecific PUCCH resource is related to beam failure recovery (BFR).

Beam failure recovery may be performed based on a PUCCH related to ascheduling request. The beam failure recovery (BFR) can also beeffectively supported for a secondary cell (SCell). In particular, whena beam failure occurs in a secondary cell (SCell) for a high frequencyband (e.g., 30 GHz), beam failure recovery can be more effectivelyperformed.

Furthermore, when a PUCCH resource related to beam failure recoveryoverlaps a PUCCH resource related to a scheduling request (e.g., an SRattributable to an event other than beam failure recovery), a PUCCHresource related to the beam failure recovery may be transmitted to havepriority. Accordingly, when an SR event and a BFR event simultaneouslyoccur, ambiguity in a UE operation can be solved, and a beam failurerecovery procedure (BFR procedure) can be more quickly initiated.

If a UE notifies a base station of only the occurrence of a beam failurethrough a PUCCH, relatively small information (e.g., 1 bit) isdelivered. In this aspect, the PUCCH needs to be transmitted using theexisting procedure.

According to an embodiment of the present disclosure, a PUCCH related tobeam failure recovery (BFR) is transmitted based on a parameter relatedto the scheduling request (SR). The parameter related to the schedulingrequest (SR) is related to at least one of a timer related to thetransmission of the SR or a maximum transmission number of the SR.Accordingly, the beam failure recovery (BFR) can be initiated based onthe existing scheduling request procedure.

If a base station is notified of only the occurrence of a beam failure,a subsequent report related to beam failure recovery needs to beperformed. According to an embodiment of the present disclosure, a UEreceives downlink control information (DCI) that schedules a PUSCHrelated to a PUCCH, and transmits the PUSCH based on the DCI. The PUSCHis related to a medium access control-control element (MAC-CE) includinginformation related to the beam failure. The MAC-CE includes informationrelated to at least one of 1) at least one secondary cell (SCell) or 2)a new beam. Accordingly, detailed information related to a beam failurecan be effectively delivered through a PUSCH scheduled based on theexisting scheduling procedure.

Effects which may be obtained by the present disclosure are not limitedto the aforementioned effects, and other technical effects not describedabove may be evidently understood by a person having ordinary skill inthe art to which the present disclosure pertains from the followingdescription.

DESCRIPTION OF DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the present disclosure and constitute a part of thedetailed description, illustrate embodiments of the present disclosureand together with the description serve to explain the principle of thepresent disclosure.

FIG. 1 is a diagram illustrating an example of an overall systemstructure of NR to which a method proposed in the present disclosure isapplicable.

FIG. 2 illustrates a relationship between an uplink frame and a downlinkframe in a wireless communication system to which a method proposed bythe present disclosure is applicable.

FIG. 3 illustrates an example of a frame structure in an NR system.

FIG. 4 illustrates an example of a resource grid supported by a wirelesscommunication system to which a method proposed in the presentdisclosure is applicable.

FIG. 5 illustrates examples of a resource grid for each antenna port andnumerology to which a method proposed in the present disclosure isapplicable.

FIG. 6 illustrates physical channels and general signal transmissionused in a 3GPP system.

FIG. 7 illustrates an example of beamforming using SSB and CSI-RS.

FIGS. 8A and 8B illustrate an example of a UL BM procedure using an SRS.

FIG. 9 illustrates an uplink transmission/reception operation to whichthe method proposed in this disclosure may be applied.

FIG. 10 illustrates an example of a random access procedure.

FIG. 11 is a diagram for explaining the concept of a threshold value foran SS block for RACH resource association.

FIG. 12 is a diagram for explaining a ramping counter of a PRACH.

FIG. 13 is a diagram for describing a beam failure recovery-relatedoperation to which a method proposed in the present disclosure may beapplied.

FIG. 14 illustrates an example of signaling between a UE/base station towhich a method proposed in the present disclosure may be applied.

FIG. 15 is a flowchart for describing a method of transmitting, by a UE,a physical uplink control channel in a wireless communication systemaccording to an embodiment of the present disclosure.

FIG. 16 is a flowchart for describing a method of receiving, by a basestation, a physical uplink control channel in a wireless communicationsystem according to another embodiment of the present disclosure.

FIG. 17 illustrates a communication system 1 applied to the presentdisclosure.

FIG. 18 illustrates wireless devices applicable to the presentdisclosure.

FIG. 19 illustrates a signal process circuit for a transmission signal.

FIG. 20 illustrates another example of a wireless device applied to thepresent disclosure.

FIG. 21 illustrates a hand-held device applied to the presentdisclosure.

DETAILED DESCRIPTION

Hereinafter, preferred embodiments of the disclosure are described indetail with reference to the accompanying drawings. The followingdetailed description taken in conjunction with the accompanying drawingsis intended for describing example embodiments of the disclosure, butnot for representing a sole embodiment of the disclosure. The detaileddescription below includes specific details to convey a thoroughunderstanding of the disclosure. However, it will be easily appreciatedby one of ordinary skill in the art that embodiments of the disclosuremay be practiced even without such details.

In some cases, to avoid ambiguity in concept, known structures ordevices may be omitted or be shown in block diagrams while focusing oncore features of each structure and device.

Hereinafter, downlink (DL) means communication from a base station to aterminal and uplink (UL) means communication from the terminal to thebase station. In the downlink, a transmitter may be part of the basestation, and a receiver may be part of the terminal. In the uplink, thetransmitter may be part of the terminal and the receiver may be part ofthe base station. The base station may be expressed as a firstcommunication device and the terminal may be expressed as a secondcommunication device. A base station (BS) may be replaced with termsincluding a fixed station, a Node B, an evolved-NodeB (eNB), a NextGeneration NodeB (gNB), a base transceiver system (BTS), an access point(AP), a network (5G network), an AI system, a road side unit (RSU), avehicle, a robot, an Unmanned Aerial Vehicle (UAV), an Augmented Reality(AR) device, a Virtual Reality (VR) device, and the like. Further, theterminal may be fixed or mobile and may be replaced with terms includinga User Equipment (UE), a Mobile Station (MS), a user terminal (UT), aMobile Subscriber Station (MSS), a Subscriber Station (SS), an AdvancedMobile Station (AMS), a Wireless Terminal (WT), a Machine-TypeCommunication (MTC) device, a Machine-to-Machine (M2M) device, and aDevice-to-Device (D2D) device, the vehicle, the robot, an AI module, theUnmanned Aerial Vehicle (UAV), the Augmented Reality (AR) device, theVirtual Reality (VR) device, and the like.

The following technology may be used in various wireless access systems,such as code division multiple access (CDMA), frequency divisionmultiple access (FDMA), time division multiple access (TDMA), orthogonalfrequency division multiple access (OFDMA), single carrier-FDMA(SC-FDMA), non-orthogonal multiple access (NOMA), and the like. The CDMAmay be implemented by radio technology such as universal terrestrialradio access (UTRA) or CDMA2000. The TDMA may be implemented by radiotechnology such as global system for mobile communications (GSM)/generalpacket radio service (GPRS)/enhanced data rates for GSM evolution(EDGE). The OFDMA may be implemented as radio technology such as IEEE802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, E-UTRA (evolved UTRA),and the like. The UTRA is a part of a universal mobile telecommunicationsystem (UMTS). 3rd generation partnership project (3GPP) long termevolution (LTE), as a part of an evolved UMTS (E-UMTS) using E-UTRA,adopts the OFDMA in the downlink and the SC-FDMA in the uplink. LTE-A(advanced) is the evolution of 3GPP LTE.

For clarity of description, the present disclosure is described based onthe 3GPP communication system (e.g., LTE-A or NR), but the technicalspirit of the present disclosure are not limited thereto. LTE meanstechnology after 3GPP TS 36.xxx Release 8. In detail, LTE technologyafter 3GPP TS 36.xxx Release 10 is referred to as the LTE-A and LTEtechnology after 3GPP TS 36.xxx Release 13 is referred to as the LTE-Apro. The 3GPP NR means technology after TS 38.xxx Release 15. The LTE/NRmay be referred to as a 3GPP system. “xxx” means a standard documentdetail number. The LTE/NR may be collectively referred to as the 3GPPsystem. Matters disclosed in a standard document published before thepresent disclosure may refer to a background art, terms, abbreviations,etc., used for describing the present disclosure. For example, thefollowing documents may be referenced.

3GPP LTE

-   -   36.211: Physical channels and modulation    -   36.212: Multiplexing and channel coding    -   36.213: Physical layer procedures    -   36.300: Overall description    -   36.331: Radio Resource Control (RRC)

3GPP NR

-   -   38.211: Physical channels and modulation    -   38.212: Multiplexing and channel coding    -   38.213: Physical layer procedures for control    -   38.214: Physical layer procedures for data    -   38.300: NR and NG-RAN Overall Description    -   36.331: Radio Resource Control (RRC) protocol specification

As more and more communication devices require larger communicationcapacity, there is a need for improved mobile broadband communicationcompared to the existing radio access technology (RAT). Further, massivemachine type communications (MTCs), which provide various servicesanytime and anywhere by connecting many devices and objects, are one ofthe major issues to be considered in the next generation communication.In addition, a communication system design considering a service/UEsensitive to reliability and latency is being discussed. As such, theintroduction of next-generation radio access technology consideringenhanced mobile broadband communication (eMBB), massive MTC (mMTC),ultra-reliable and low latency communication (URLLC) is discussed, andin the present disclosure, the technology is called NR for convenience.The NR is an expression representing an example of 5G radio accesstechnology (RAT).

Three major requirement areas of 5G include (1) an enhanced mobilebroadband (eMBB) area, (2) a massive machine type communication (mMTC)area and (3) a ULtra-reliable and low latency communications (URLLC)area.

Some use cases may require multiple areas for optimization, and otheruse case may be focused on only one key performance indicator (KPI). 5Gsupport such various use cases in a flexible and reliable manner.

eMBB is far above basic mobile Internet access and covers media andentertainment applications in abundant bidirectional tasks, cloud oraugmented reality. Data is one of key motive powers of 5G, and dedicatedvoice services may not be first seen in the 5G era. In 5G, it isexpected that voice will be processed as an application program using adata connection simply provided by a communication system. Major causesfor an increased traffic volume include an increase in the content sizeand an increase in the number of applications that require a high datatransfer rate. Streaming service (audio and video), dialogue type videoand mobile Internet connections will be used more widely as more devicesare connected to the Internet. Such many application programs requireconnectivity always turned on in order to push real-time information andnotification to a user. A cloud storage and application suddenlyincreases in the mobile communication platform, and this may be appliedto both business and entertainment. Furthermore, cloud storage is aspecial use case that tows the growth of an uplink data transfer rate.5G is also used for remote business of cloud. When a tactile interfaceis used, further lower end-to-end latency is required to maintainexcellent user experiences. Entertainment, for example, cloud game andvideo streaming are other key elements which increase a need for themobile broadband ability. Entertainment is essential in the smartphoneand tablet anywhere including high mobility environments, such as atrain, a vehicle and an airplane. Another use case is augmented realityand information search for entertainment. In this case, augmentedreality requires very low latency and an instant amount of data.

Furthermore, one of the most expected 5G use case relates to a functioncapable of smoothly connecting embedded sensors in all fields, that is,mMTC. Until 2020, it is expected that potential IoT devices will reach20.4 billions. The industry IoT is one of areas in which 5G performsmajor roles enabling smart city, asset tracking, smart utility,agriculture and security infra.

URLLC includes a new service which will change the industry throughremote control of major infra and a link having ultra reliability/lowavailable latency, such as a self-driving vehicle. A level ofreliability and latency is essential for smart grid control, industryautomation, robot engineering, drone control and adjustment.

Multiple use cases are described more specifically.

5G may supplement fiber-to-the-home (FTTH) and cable-based broadband (orDOCSIS) as means for providing a stream evaluated from gigabits persecond to several hundreds of mega bits per second. Such fast speed isnecessary to deliver TV with resolution of 4K or more (6K, 8K or more)in addition to virtual reality and augmented reality. Virtual reality(VR) and augmented reality (AR) applications include immersive sportsgames. A specific application program may require a special networkconfiguration. For example, in the case of VR game, in order for gamecompanies to minimize latency, a core server may need to be integratedwith the edge network server of a network operator.

An automotive is expected to be an important and new motive power in 5G,along with many use cases for the mobile communication of an automotive.For example, entertainment for a passenger requires a high capacity anda high mobility mobile broadband at the same time. The reason for thisis that future users continue to expect a high-quality connectionregardless of their location and speed. Another use example of theautomotive field is an augmented reality dashboard. The augmentedreality dashboard overlaps and displays information, identifying anobject in the dark and notifying a driver of the distance and movementof the object, over a thing seen by the driver through a front window.In the future, a wireless module enables communication betweenautomotives, information exchange between an automotive and a supportedinfrastructure, and information exchange between an automotive and otherconnected devices (e.g., devices accompanied by a pedestrian). A safetysystem guides alternative courses of a behavior so that a driver maydrive more safely, thereby reducing a danger of an accident. A next stepwill be a remotely controlled or self-driven vehicle. This requires veryreliable, very fast communication between different self-driven vehiclesand between an automotive and infra. In the future, a self-drivenvehicle may perform all driving activities, and a driver will be focusedon things other than traffic, which cannot be identified by anautomotive itself. Technical requirements of a self-driven vehiclerequire ultra-low latency and ultra-high speed reliability so thattraffic safety is increased up to a level which cannot be achieved by aperson.

A smart city and smart home mentioned as a smart society will beembedded as a high-density radio sensor network. The distributed networkof intelligent sensors will identify the cost of a city or home and acondition for energy-efficient maintenance. A similar configuration maybe performed for each home. All of a temperature sensor, a window andheating controller, a burglar alarm and home appliances are wirelesslyconnected. Many of such sensors are typically a low data transfer rate,low energy and a low cost. However, for example, real-time HD video maybe required for a specific type of device for surveillance.

The consumption and distribution of energy including heat or gas arehighly distributed and thus require automated control of a distributedsensor network. A smart grid collects information, and interconnectssuch sensors using digital information and a communication technology sothat the sensors operate based on the information. The information mayinclude the behaviors of a supplier and consumer, and thus the smartgrid may improve the distribution of fuel, such as electricity, in anefficient, reliable, economical, production-sustainable and automatedmanner. The smart grid may be considered to be another sensor networkhaving small latency.

A health part owns many application programs which reap the benefits ofmobile communication. A communication system may support remotetreatment providing clinical treatment at a distant place. This helps toreduce a barrier for the distance and may improve access to medicalservices which are not continuously used at remote farming areas.Furthermore, this is used to save life in important treatment and anemergency condition. A radio sensor network based on mobilecommunication may provide remote monitoring and sensors for parameters,such as the heart rate and blood pressure.

Radio and mobile communication becomes increasingly important in theindustry application field. Wiring requires a high installation andmaintenance cost. Accordingly, the possibility that a cable will bereplaced with reconfigurable radio links is an attractive opportunity inmany industrial fields. However, to achieve the possibility requiresthat a radio connection operates with latency, reliability and capacitysimilar to those of the cable and that management is simplified. Lowlatency and a low error probability is a new requirement for aconnection to 5G.

Logistics and freight tracking is an important use case for mobilecommunication, which enables the tracking inventory and packagesanywhere using a location-based information system. The logistics andfreight tracking use case typically requires a low data speed, but awide area and reliable location information.

In a New RAT system including NR uses an OFDM transmission scheme or asimilar transmission scheme thereto. The new RAT system may follow OFDMparameters different from OFDM parameters of LTE. Alternatively, the newRAT system may follow numerology of conventional LTE/LTE-A as it is orhave a larger system bandwidth (e.g., 100 MHz). Alternatively, one cellmay support a plurality of numerologies. In other words, UEs thatoperate with different numerologies may coexist in one cell.

The numerology corresponds to one subcarrier spacing in a frequencydomain. By scaling a reference subcarrier spacing by an integer N,different numerologies may be defined.

Definition of Terms

eLTE eNB: The eLTE eNB is the evolution of eNB that supportsconnectivity to EPC and NGC.

gNB: A node which supports the NR as well as connectivity to NGC.

New RAN: A radio access network which supports either NR or E-UTRA orinterfaces with the NGC.

Network slice: A network slice is a network defined by the operatorcustomized to provide an optimized solution for a specific marketscenario which demands specific requirements with end-to-end scope.

Network function: A network function is a logical node within a networkinfrastructure that has well-defined external interfaces andwell-defined functional behavior.

NG-C: A control plane interface used at an NG2 reference point betweennew RAN and NGC.

NG-U: A user plane interface used at an NG3 reference point between newRAN and NGC.

Non-standalone NR: A deployment configuration where the gNB requires anLTE eNB as an anchor for control plane connectivity to EPC, or requiresan eLTE eNB as an anchor for control plane connectivity to NGC.

Non-standalone E-UTRA: A deployment configuration where the eLTE eNBrequires a gNB as an anchor for control plane connectivity to NGC.

User plane gateway: An end point of NG-U interface.

Overview of System

FIG. 1 illustrates an example overall NR system structure to which amethod as proposed in the disclosure may apply.

Referring to FIG. 1 , an NG-RAN is constituted of gNBs to provide acontrol plane (RRC) protocol end for user equipment (UE) and NG-RA userplane (new AS sublayer/PDCP/RLC/MAC/PHY).

The gNBs are mutually connected via an Xn interface.

The gNBs are connected to the NGC via the NG interface.

More specifically, the gNB connects to the access and mobilitymanagement function (AMF) via the N2 interface and connects to the userplane function (UPF) via the N3 interface.

New RAT (NR) Numerology and Frame Structure

In the NR system, a number of numerologies may be supported. Here, thenumerology may be defined by the subcarrier spacing and cyclic prefix(CP) overhead. At this time, multiple subcarrier spacings may be derivedby scaling the basic subcarrier spacing by integer N (or, μ). Further,although it is assumed that a very low subcarrier spacing is not used ata very high carrier frequency, the numerology used may be selectedindependently from the frequency band.

Further, in the NR system, various frame structures according tomultiple numerologies may be supported.

Hereinafter, an orthogonal frequency division multiplexing (OFDM)numerology and frame structure that may be considered in the NR systemis described.

The multiple OFDM numerologies supported in the NR system may be definedas shown in Table 1.

TABLE 1 μ Δf = 2^(μ) · 15[kHz] Cyclic prefix 0 15 Normal 1 30 Normal 260 Normal, Extended 3 120 Normal 4 240 Normal

NR supports multiple numerologies (or subcarrier spacings (SCS)) forsupporting various 5G services. For example, if SCS is 15 kHz, NRsupports a wide area in typical cellular bands. If SCS is 30 kHz/60 kHz,NR supports a dense urban, lower latency and a wider carrier bandwidth.If SCS is 60 kHz or higher, NR supports a bandwidth greater than 24.25GHz in order to overcome phase noise.

An NR frequency band is defined as a frequency range of two types FR1and FR2. The FR1 and the FR2 may be configured as in Table 1 below.Furthermore, the FR2 may mean a millimeter wave (mmW).

TABLE 2 Frequency Range Corresponding frequency designation rangeSubcarrier Spacing FR1  410 MHz-7125 MHz 15, 30, 60 kHz FR2 24250MHz-52600 MHz 60, 120, 240 kHz

With regard to the frame structure in the NR system, the size of variousfields in the time domain is expressed as a multiple of time unit ofT_(s)=1/(Δf_(max)·N_(f)), where Δf_(max)=480·10³, and N_(f)=4096.Downlink and uplink transmissions is constituted of a radio frame with aperiod of T_(f)=(Δf_(max)N_(f)/100)·T_(s)=10 ms. Here, the radio frameis constituted of 10 subframes each of which has a period ofT_(sf)=(Δf_(max)N_(f)/1000)·T_(s)=1 ms. In this case, one set of framesfor uplink and one set of frames for downlink may exist.

FIG. 2 illustrates a relationship between an uplink frame and downlinkframe in a wireless communication system to which a method described inthe present disclosure is applicable.

As illustrated in FIG. 2 , uplink frame number i for transmission fromthe user equipment (UE) should begin T_(TA)=N_(TA)T_(s) earlier than thestart of the downlink frame by the UE.

For numerology μ, slots are numbered in ascending order of n_(s)^(μ∈{)0, . . . , N_(subframe) ^(slots,μ)−1} in the subframe and inascending order of n_(s,f) ^(μ)∈{0, . . . , N_(frame) ^(slots,μ)−1} inthe radio frame. One slot includes consecutive OFDM symbols of N_(symb)^(μ), and N_(symb) ^(μ) is determined according to the used numerologyand slot configuration. In the subframe, the start of slot n_(s) ^(μ) istemporally aligned with the start of n_(s) ^(μ)N_(symb) ^(μ).

Not all UEs are able to transmit and receive at the same time, and thismeans that not all OFDM symbols in a downlink slot or an uplink slot areavailable to be used.

Table 3 represents the number N_(symb) ^(slot) of OFDM symbols per slot,the number N_(slot) ^(frame,μ) of slots per radio frame, and the numberN_(slot) ^(subframe,μ) of slots per subframe in a normal CP. Table 4represents the number of OFDM symbols per slot, the number of slots perradio frame, and the number of slots per subframe in an extended CP.

TABLE 3 μ N_(symb) ^(slot) N_(slot) ^(frame, μ) N_(slot) ^(subframe, μ)0 14 10 1 1 14 20 2 2 14 40 4 3 14 80 8 4 14 160 16

TABLE 4 μ N_(symb) ^(slot) N_(slot) ^(frame, μ) N_(slot) ^(subframe, μ)2 12 40 4

FIG. 3 illustrates an example of a frame structure in a NR system. FIG.3 is merely for convenience of explanation and does not limit the scopeof the present disclosure.

In Table 4, in case of μ=2, i.e., as an example in which a subcarrierspacing (SCS) is 60 kHz, one subframe (or frame) may include four slotswith reference to Table 3, and one subframe={1, 2, 4} slots shown inFIG. 3 , for example, the number of slot(s) that may be included in onesubframe may be defined as in Table 3.

Further, a mini-slot may consist of 2, 4, or 7 symbols, or may consistof more symbols or less symbols.

In regard to physical resources in the NR system, an antenna port, aresource grid, a resource element, a resource block, a carrier part,etc. May be considered.

Hereinafter, the above physical resources that may be considered in theNR system are described in more detail.

First, in regard to an antenna port, the antenna port is defined so thata channel over which a symbol on an antenna port is conveyed may beinferred from a channel over which another symbol on the same antennaport is conveyed. When large-scale properties of a channel over which asymbol on one antenna port is conveyed may be inferred from a channelover which a symbol on another antenna port is conveyed, the two antennaports may be regarded as being in a quasi co-located or quasico-location (QC/QCL) relation. Here, the large-scale properties mayinclude at least one of delay spread, Doppler spread, frequency shift,average received power, and received timing.

FIG. 4 illustrates an example of a resource grid supported in a wirelesscommunication system to which a method proposed in the presentdisclosure is applicable.

Referring to FIG. 4 , a resource grid consists of N_(RB) ^(μ)N_(sc)^(RB) subcarriers on a frequency domain, each subframe consisting of14·2μ OFDM symbols, but the present disclosure is not limited thereto.

In the NR system, a transmitted signal is described by one or moreresource grids, consisting of N_(RB) ^(μ)N_(sc) ^(RB) subcarriers, and2^(μ)N_(symb) ^((μ)) OFDM symbols, where N_(RB) ^(μ)≤N_(RB) ^(max,μ).N_(RB) ^(max,μ) denotes a maximum transmission bandwidth and may changenot only between numerologies but also between uplink and downlink.

In this case, as illustrated in FIG. 5 , one resource grid may beconfigured per numerology μ and antenna port p.

FIG. 5 illustrates examples of a resource grid per antenna port andnumerology to which a method proposed in the present disclosure isapplicable.

Each element of the resource grid for the numerology μ and the antennaport p is called a resource element and is uniquely identified by anindex pair (k, l), where k=0, . . . , N_(RB) ^(μ)N_(sc) ^(RB)−1 is anindex on a frequency domain, and l=0, . . . , 2^(μ)N_(symb) ^((μ))−1refers to a location of a symbol in a subframe. The index pair (k,l) isused to refer to a resource element in a slot, where l=0, . . . ,N_(symb) ^(μ)−1.

The resource element (k, l) for the numerology μ and the antenna port pcorresponds to a complex value a_(k,l) ^((p,μ)). When there is no riskfor confusion or when a specific antenna port or numerology is notspecified, the indexes p and μ may be dropped, and as a result, thecomplex value may be a_(k,l) ^((p)) or a_(k,l) .

Further, a physical resource block is defined as N_(sc) ^(RB)=12consecutive subcarriers in the frequency domain.

Point A serves as a common reference point of a resource block grid andmay be obtained as follows.

-   -   offsetToPointA for PCell downlink represents a frequency offset        between the point A and a lowest subcarrier of a lowest resource        block that overlaps a SS/PBCH block used by the UE for initial        cell selection, and is expressed in units of resource blocks        assuming 15 kHz subcarrier spacing for FR1 and 60 kHz subcarrier        spacing for FR2;    -   absoluteFrequencyPointA represents frequency-location of the        point A expressed as in absolute radio-frequency channel number        (ARFCN).

The common resource blocks are numbered from 0 and upwards in thefrequency domain for subcarrier spacing configuration μ.

The center of subcarrier 0 of common resource block 0 for the subcarrierspacing configuration μ coincides with ‘point A’. A common resourceblock number n_(CRB) ^(μ) in the frequency domain and resource elements(k, l) for the subcarrier spacing configuration μ may be given by thefollowing Equation 1.

$\begin{matrix}{n_{CRB}^{\mu} = \left\lfloor \frac{k}{N_{sc}^{BB}} \right\rfloor} & \left\lbrack {{Equation}1} \right\rbrack\end{matrix}$

Here, k may be defined relative to the point A so that k=0 correspondsto a subcarrier centered around the point A. Physical resource blocksare defined within a bandwidth part (BWP) and are numbered from 0 toN_(BWP,i) ^(size)−1, where i is No. Of the BWP. A relation between thephysical resource block n_(PRB) in BWP i and the common resource blockn_(CRB) may be given by the following Equation 2.n _(CRB) =n _(PRB) +N _(BWP,i) ^(start)  [Equation 2]

Here, N_(BWP,i) ^(start) may be the common resource block where the BWPstarts relative to the common resource block 0.

Physical Channel and General Signal Transmission

FIG. 6 illustrates physical channels and general signal transmissionused in a 3GPP system. In a wireless communication system, the UEreceives information from the eNB through Downlink (DL) and the UEtransmits information from the eNB through Uplink (UL). The informationwhich the eNB and the UE transmit and receive includes data and variouscontrol information and there are various physical channels according toa type/use of the information which the eNB and the UE transmit andreceive.

When the UE is powered on or newly enters a cell, the UE performs aninitial cell search operation such as synchronizing with the eNB (S601).To this end, the UE may receive a Primary Synchronization Signal (PSS)and a (Secondary Synchronization Signal (SSS) from the eNB andsynchronize with the eNB and acquire information such as a cell ID orthe like. Thereafter, the UE may receive a Physical Broadcast Channel(PBCH) from the eNB and acquire in-cell broadcast information.Meanwhile, the UE receives a Downlink Reference Signal (DL RS) in aninitial cell search step to check a downlink channel status.

A UE that completes the initial cell search receives a Physical DownlinkControl Channel (PDCCH) and a Physical Downlink Control Channel (PDSCH)according to information loaded on the PDCCH to acquire more specificsystem information (S602).

Meanwhile, when there is no radio resource first accessing the eNB orfor signal transmission, the UE may perform a Random Access Procedure(RACH) to the eNB (S603 to S606). To this end, the UE may transmit aspecific sequence to a preamble through a Physical Random Access Channel(PRACH) (S603 and S605) and receive a response message (Random AccessResponse (RAR) message) for the preamble through the PDCCH and acorresponding PDSCH. In the case of a contention based RACH, aContention Resolution Procedure may be additionally performed (S606).

The UE that performs the above procedure may then perform PDCCH/PDSCHreception (S607) and Physical Uplink Shared Channel (PUSCH)/PhysicalUplink Control Channel (PUCCH) transmission (S608) as a generaluplink/downlink signal transmission procedure. In particular, the UE mayreceive Downlink Control Information (DCI) through the PDCCH. Here, theDCI may include control information such as resource allocationinformation for the UE and formats may be differently applied accordingto a use purpose.

Meanwhile, the control information which the UE transmits to the eNBthrough the uplink or the UE receives from the eNB may include adownlink/uplink ACK/NACK signal, a Channel Quality Indicator (CQI), aPrecoding Matrix Index (PMI), a Rank Indicator (RI), and the like. TheUE may transmit the control information such as the CQI/PMI/RI, etc.,through the PUSCH and/or PUCCH.

Beam Management (BM)

A BM procedure as layer 1 (L1)/layer 2 (L2) procedures for acquiring andmaintaining a set of base station (e.g., gNB, TRP, etc.) and/or terminal(e.g., UE) beams which may be used for downlink (DL) and uplink (UL)transmission/reception may include the following procedures and terms.

-   -   Beam measurement: Operation of measuring characteristics of a        beam forming signal received by the eNB or UE.    -   Beam determination: Operation of selecting a transmit (Tx)        beam/receive (Rx) beam of the eNB or UE by the eNB or UE.    -   Beam sweeping: Operation of covering a spatial region using the        transmit and/or receive beam for a time interval by a        predetermined scheme.    -   Beam report: Operation in which the UE reports information of a        beamformed signal based on beam measurement.

The BM procedure may be divided into (1) a DL BM procedure using asynchronization signal (SS)/physical broadcast channel (PBCH) Block orCSI-RS and (2) a UL BM procedure using a sounding reference signal(SRS). Further, each BM procedure may include Tx beam sweeping fordetermining the Tx beam and Rx beam sweeping for determining the Rxbeam.

Downlink Beam Management (DL BM)

The DL BM procedure may include (1) transmission of beamformed DLreference signals (RSs) (e.g., CIS-RS or SS Block (SSB)) of the eNB and(2) beam reporting of the UE.

Here, the beam reporting a preferred DL RS identifier (ID)(s) andL1-Reference Signal Received Power (RSRP).

The DL RS ID may be an SSB Resource Indicator (SSBRI) or a CSI-RSResource Indicator (CRI).

FIG. 7 illustrates an example of beamforming using a SSB and a CSI-RS.

As illustrated in FIG. 7 , a SSB beam and a CSI-RS beam may be used forbeam measurement. A measurement metric is L1-RSRP per resource/block.The SSB may be used for coarse beam measurement, and the CSI-RS may beused for fine beam measurement. The SSB may be used for both Tx beamsweeping and Rx beam sweeping. The Rx beam sweeping using the SSB may beperformed while the UE changes Rx beam for the same SSBRI acrossmultiple SSB bursts. One SS burst includes one or more SSBs, and one SSburst set includes one or more SSB bursts.

DL BM Related Beam Indication

A UE may be RRC-configured with a list of up to M candidate transmissionconfiguration indication (TCI) states at least for the purpose of quasico-location (QCL) indication, where M may be 64.

Each TCI state may be configured with one RS set. Each ID of DL RS atleast for the purpose of spatial QCL (QCL Type D) in an RS set may referto one of DL RS types such as SSB, P-CSI RS, SP-CSI RS, A-CSI RS, etc.

Initialization/update of the ID of DL RS(s) in the RS set used at leastfor the purpose of spatial QCL may be performed at least via explicitsignaling.

Table 5 represents an example of TCI-State IE.

The TCI-State IE associates one or two DL reference signals (RSs) withcorresponding quasi co-location (QCL) types.

TABLE 5 -- ASN1START -- TAG-TCI-STATE-START TCI-State ::=   SEQUENCE { tci-StateId    TCI-StateId,  qcl-Type1    QCL-Info,  qcl-Type2   QCL-Info OPTIONAL, -- Need R  ... } QCL-Info ::=   SEQUENCE {  cell    ServCellIndex  OPTIONAL, -- Need R  bwp-Id     BWP-Id  OPTIONAL, --Cond CSI-RS-ResourceId,  referenceSignal    CHOICE {   csi-rs    NZP-CSI-RS-ResourceId,   ssb      SSB-Index  },  qcl-Type   ENUMERATED {typeA, typeB, typeC,    typeD},  ... } --TAG-TCI-STATE-STOP -- ASN1STOP

In Table 5, bwp-Id parameter represents a DL BWP where the RS islocated, cell parameter represents a carrier where the RS is located,and reference signal parameter represents reference antenna port(s)which is a source of quasi co-location for corresponding target antennaport(s) or a reference signal including the one. The target antennaport(s) may be CSI-RS, PDCCH DMRS, or PDSCH DMRS. As an example, inorder to indicate QCL reference RS information on NZP CSI-RS, thecorresponding TCI state ID may be indicated to NZP CSI-RS resourceconfiguration information. As another example, in order to indicate QCLreference information on PDCCH DMRS antenna port(s), the TCI state IDmay be indicated to each CORESET configuration. As another example, inorder to indicate QCL reference information on PDSCH DMRS antennaport(s), the TCI state ID may be indicated via DCI.

Quasi-Co Location (QCL)

The antenna port is defined so that a channel over which a symbol on anantenna port is conveyed may be inferred from a channel over whichanother symbol on the same antenna port is conveyed. When properties ofa channel over which a symbol on one antenna port is conveyed may beinferred from a channel over which a symbol on another antenna port isconveyed, the two antenna ports may be considered as being in a quasico-located or quasi co-location (QC/QCL) relationship.

The channel properties include one or more of delay spread, Dopplerspread, frequency/Doppler shift, average received power, receivedtiming/average delay, and spatial RX parameter. The spatial Rx parametermeans a spatial (reception) channel property parameter such as an angleof arrival.

The UE may be configured with a list of up to M TCI-State configurationswithin the higher layer parameter PDSCH-Config to decode PDSCH accordingto a detected PDCCH with DCI intended for the corresponding UE and agiven serving cell, where M depends on UE capability.

Each TCI-State contains parameters for configuring a quasi co-locationrelationship between one or two DL reference signals and the DM-RS portsof the PDSCH.

The quasi co-location relationship is configured by the higher layerparameter qcl-Type1 for the first DL RS and qcl-Type2 for the second DLRS (if configured). For the case of two DL RSs, the QCL types are not bethe same, regardless of whether the references are to the same DL RS ordifferent DL RSs.

The quasi co-location types corresponding to each DL RS are given by thehigher layer parameter qcl-Type of QCL-Info and may take one of thefollowing values:

-   -   ‘QCL-TypeA’: (Doppler shift, Doppler spread, average delay,        delay spread)    -   ‘QCL-TypeB’: (Doppler shift, Doppler spread)    -   ‘QCL-TypeC’: (Doppler shift, average delay)    -   ‘QCL-TypeD’: (Spatial Rx parameter)

For example, if a target antenna port is a specific NZP CSI-RS, thecorresponding NZP CSI-RS antenna ports may be indicated/configured to beQCLed with a specific TRS in terms of QCL-TypeA and with a specific SSBin terms of QCL-TypeD. The UE receiving the indication/configuration mayreceive the corresponding NZP CSI-RS using the Doppler or delay valuemeasured in the QCL-TypeA TRS and apply the Rx beam used for QCL-TypeDSSB reception to the reception of the corresponding NZP CSI-RSreception.

The UE may receive an activation command by MAC CE signaling used to mapup to eight TCI states to the codepoint of the DCI field ‘TransmissionConfiguration Indication’.

UL BM Procedure

A UL BM may be configured such that beam reciprocity (or beamcorrespondence) between Tx beam and Rx beam is established or notestablished depending on the UE implementation. If the beam reciprocitybetween Tx beam and Rx beam is established in both a base station and aUE, a UL beam pair may be adjusted via a DL beam pair. However, if thebeam reciprocity between Tx beam and Rx beam is not established in anyone of the base station and the UE, a process for determining the ULbeam pair is necessary separately from determining the DL beam pair.

Even when both the base station and the UE maintain the beamcorrespondence, the base station may use a UL BM procedure fordetermining the DL Tx beam even if the UE does not request a report of a(preferred) beam.

The UM BM may be performed via beamformed UL SRS transmission, andwhether to apply UL BM of a SRS resource set is configured by the(higher layer parameter) usage. If the usage is set to ‘BeamManagement(BM)’, only one SRS resource may be transmitted to each of a pluralityof SRS resource sets in a given time instant.

The UE may be configured with one or more sounding reference symbol(SRS) resource sets configured by (higher layer parameter)SRS-ResourceSet (via higher layer signaling, RRC signaling, etc.). Foreach SRS resource set, the UE may be configured with K≥1 SRS resources(higher later parameter SRS-resource), where K is a natural number, anda maximum value of K is indicated by SRS_capability.

In the same manner as the DL BM, the UL BM procedure may be divided intoa UE's Tx beam sweeping and a base station's Rx beam sweeping.

FIGS. 8A and 8B illustrate an example of a UL BM procedure using a SRS.

More specifically, FIG. 8A illustrates an Rx beam determinationprocedure of a base station, and FIG. 8A illustrates a Tx beam sweepingprocedure of a UE.

FIG. 9 illustrates an uplink transmission/reception operation to whichthe method proposed in this disclosure may be applied.

Referring to FIG. 9 , a BS schedules uplink transmission such as afrequency/time resource, a transport layer, an uplink precoder, and anMCS (S910). In particular, the BS may determine a beam for a UE totransmit a PUSCH.

The UE receives a DCI for uplink scheduling (i.e., including schedulinginformation of the PUSCH) on a PDCCH from the BS (S920).

For uplink scheduling, DCI format 0_0 or 0_1 may be used. In particular,DCI format 0_1 includes the following information.

DCI format identifier (identifier for DCI formats), UL/SUL(supplementary uplink) indicator (UL/SUL indicator), bandwidth partindicator, frequency domain resource assignment, time domain resourceassignment, frequency hopping flag, modulation and coding scheme (MCS),SRS resource indicator (SRI), precoding information and number oflayers, antenna port(s), SRS request, DMRS sequence initialization,uplink shared channel (UL-SCH) indicator.

In particular, SRS resources configured in the SRS resource setassociated with the higher layer parameter ‘usage’ may be indicated byan SRS resource indicator field. In addition, ‘spatialRelationInfo’ maybe set for each SRS resource, and the value may be one of {CRI, SSB,SRI}.

The UE transmits uplink data to the BS on PUSCH (S930).

When the UE detects a PDCCH including DCI format 0_0 or 0_1, ittransmits a corresponding PUSCH according to an indication by thecorresponding DCI.

For PUSCH transmission, two transmission schemes are supported:codebook-based transmission and non-codebook-based transmission.

i) When the higher layer parameter ‘txConfig’ is set to ‘codebook’, theUE is set to codebook-based transmission. Meanwhile, when the higherlayer parameter ‘txConfig’ is set to ‘nonCodebook’, the UE is set tonon-codebook-based transmission. If the higher layer parameter‘txConfig’ is not set, the UE does not expect to be scheduled by DCIformat 0_1. When the PUSCH is scheduled by DCI format 0_0, PUSCHtransmission is based on a single antenna port.

In the case of codebook-based transmission, the PUSCH may be scheduledby DCI format 0_0, DCI format 0_1 or semi-statically. When the PUSCH isscheduled by DCI format 0_1, the UE determines a PUSCH transmissionprecoder based on SRI, TPMI (Transmit Precoding Matrix Indicator) andtransmission rank from DCI, as given by the SRS resource indicator fieldand the precoding information and number of layers field. The TPMI isused to indicate a precoder to be applied across an antenna port, andcorresponds to an SRS resource selected by the SRI when multiple SRSresources are configured. Alternatively, when a single SRS resource isconfigured, the TPMI is used to indicate a precoder to be applied acrossthe antenna port and corresponds to the single SRS resource. Atransmission precoder is selected from the uplink codebook having thesame number of antenna ports as the higher layer parameter‘nrofSRS-Ports’.

When the higher layer parameter ‘txConfig’ set to ‘codebook’ in the UEis configured, at least one SRS resource is configured in the UE. TheSRI indicated in slot n is associated with the latest transmission ofthe SRS resource identified by the SRI, and here, the SRS resourceprecedes a PDCCH carrying the SRI (i.e., slot n).

ii) In the case of non-codebook-based transmission, the PUSCH may bescheduled by DCI format 0_0, DCI format 0_1 or semi-statically. Whenmultiple SRS resources are configured, the UE may determine the PUSCHprecoder and transmission rank based on the wideband SRI, and here, theSRI is given by the SRS resource indicator in the DCI or by the higherlayer parameter ‘srs-ResourceIndicator’. The UE uses one or multiple SRSresources for SRS transmission, and here, the number of SRS resourcesmay be configured for simultaneous transmission within the same RB basedon UE capability. Only one SRS port is configured for each SRS resource.Only one SRS resource may be set as the higher layer parameter ‘usage’set to ‘nonCodebook’. The maximum number of SRS resources that may beconfigured for non-codebook-based uplink transmission is 4. The SRIindicated in slot n is associated with the latest transmission of theSRS resource identified by the SRI, and here, the SRS transmissionprecedes the PDCCH carrying the SRI (i.e., slot n).

Random Access Related Procedure

The random access procedure of the UE can be summarized in Table 6 andFIG. 10 .

TABLE 6 Operations/Information Type of Signals Acquired 1^(st) PRACHpreamble * Initial beam acquisition step in UL * Random election ofRA-preamble ID 2^(nd) Random Access * Timing alignment information StepResponse * RA-preamble ID on DL-SCH * Initial UL grant, Temporary C-RNTI3^(rd) UL transmission * RRC connection request Step on UL-SCH * UEidentifier 4^(th) Contention * Temporary C-RNTI on PDCCH for StepResolution initial access on DL * C-RNTI on PDCCH for UE inRRC_CONNECTED

FIG. 10 illustrates an example of a random access procedure.

Firstly, the UE may transmit PRACH preamble in UL as Msg1 of the randomaccess procedure.

Random access preamble sequences, of two different lengths aresupported. Long sequence length 839 is applied with subcarrier spacingsof 1.25 and 5 kHz and short sequence length 139 is applied withsub-carrier spacings 15, 30, 60 and 120 kHz. Long sequences supportunrestricted sets and restricted sets of Type A and Type B, while shortsequences support unrestricted sets only.

Multiple RACH preamble formats are defined with one or more RACH OFDMsymbols, and different cyclic prefix and guard time. The PRACH preambleconfiguration to use is provided to the UE in the system information.

When there is no response to the Msg1, the UE may retransmit the PRACHpreamble with power ramping within the prescribed number of times. TheUE calculates the PRACH transmit power for the retransmission of thepreamble based on the most recent estimate pathloss and power rampingcounter. If the UE conducts beam switching, the counter of power rampingremains unchanged.

The system information informs the UE of the association between the SSblocks and the RACH resources.

FIG. 11 is a diagram for explaining the concept of a threshold value foran SS block for RACH resource association.

The threshold of the SS block for RACH resource association is based onthe RSRP and network configurable. Transmission or retransmission ofRACH preamble is based on the SS blocks that satisfy the threshold.

When the UE receives random access response on DL-SCH, the DL-SCH mayprovide timing alignment information, RA-preamble ID, initial UL grantand Temporary C-RNTI.

Based on this information, the UE may transmit UL transmission on UL-SCHas Msg3 of the random access procedure. Msg3 can include RRC connectionrequest and UE identifier.

In response, the network may transmit Msg4, which can be treated ascontention resolution message on DL. By receiving this, the UE may enterinto RRC connected state.

Specific explanation for each of the steps is as follows:

Prior to initiation of the physical random access procedure, Layer 1shall receive from higher layers a set of SS/PBCH block indexes andshall provide to higher layers a corresponding set of RSRP measurements.

Prior to initiation of the physical random access procedure, Layer 1shall receive the following information from the higher layers:

-   -   Configuration of physical random access channel (PRACH)        transmission parameters (PRACH preamble format, time resources,        and frequency resources for PRACH transmission).    -   Parameters for determining the root sequences and their cyclic        shifts in the PRACH preamble sequence set (index to logical root        sequence table, cyclic shift (N_(CS)), and set type        (unrestricted, restricted set A, or restricted set B)).

From the physical layer perspective, the L1 random access procedureencompasses the transmission of random access preamble (Msg1) in aPRACH, random access response (RAR) message with a PDCCH/PDSCH (Msg2),and when applicable, the transmission of Msg3 PUSCH, and PDSCH forcontention resolution.

If a random access procedure is initiated by a “PDCCH order” to the UE,a random access preamble transmission is with a same subcarrier spacingas a random access preamble transmission initiated by higher layers.

If a UE is configured with two UL carriers for a serving cell and the UEdetects a “PDCCH order”, the UE uses the UL/SUL indicator field valuefrom the detected “PDCCH order” to determine the UL carrier for thecorresponding random access preamble transmission.

Regarding the random access preamble transmission step, physical randomaccess procedure is triggered upon request of a PRACH transmission byhigher layers or by a PDCCH order. A configuration by higher layers fora PRACH transmission includes the following:

-   -   A configuration for PRACH transmission.    -   A preamble index, a preamble subcarrier spacing,        P_(PRACHtarget), a corresponding RA-RNTI, and a PRACH resource.

A preamble is transmitted using the selected PRACH format withtransmission power P_(PRACH2,f,c)(i), on the indicated PRACH resource.

A UE is provided a number of SS/PBCH blocks associated with one PRACHoccasion by the value of higher layer parameter SSB-perRACH-Occasion. Ifthe value of SSB-perRACH-Occasion is smaller than one, one SS/PBCH blockis mapped to 1/SSB-per-rach-occasion consecutive PRACH occasions. The UEis provided a number of preambles per SS/PBCH block by the value ofhigher layer parameter cb-preamblePerSSB and the UE determines a totalnumber of preambles per SSB per PRACH occasion as the multiple of thevalue of SSB-perRACH-Occasion and the value of cb-preamblePerSSB.

SS/PBCH block indexes are mapped to PRACH occasions in the followingorder.

-   -   First, in increasing order of preamble indexes within a single        PRACH occasion.    -   Second, in increasing order of frequency resource indexes for        frequency multiplexed PRACH occasions.    -   Third, in increasing order of time resource indexes for time        multiplexed PRACH occasions within a PRACH slot.    -   Fourth, in increasing order of indexes for PRACH slots.

The period, starting from frame 0, for the mapping of SS/PBCH blocks toPRACH occasions is the smallest of {1, 2, 4} PRACH configuration periodsthat is larger than or equal to ┌N_(Tx) ^(SSB)/N_(PRACH period) ^(SSB)┐,where the UE obtains N_(Tx) ^(SSB) from higher layer parameterSSB-transmitted-SIB1 and N_(PRACHperiod) ^(SSB) is the number of SS/PBCHblocks that can be mapped to one PRACH configuration period.

If a random access procedure is initiated by a PDCCH order, the UEshall, if requested by higher layers, transmit a PRACH in the firstavailable PRACH occasion for which a time between the last symbol of thePDCCH order reception and the first symbol of the PRACH transmission islarger than or equal to N_(T,2)+Δ_(BWPSwitching)+Δ_(Delay) msec whereN_(T,2) is a time duration of N₂ symbols corresponding to a PUSCHpreparation time for PUSCH processing capability 1, Δ_(BWPSwitching) ispre-defined, and Δ_(Delay)>0.

In response to a PRACH transmission, a UE attempts to detect a PDCCHwith a corresponding RA-RNTI during a window controlled by higherlayers. The window starts at the first symbol of the earliest controlresource set the UE is configured for Type1-PDCCH common search spacethat is at least ┌(Δ·N_(slot) ^(subframe,μ)·N_(symb) ^(slot))/T_(sf)┐symbols after the last symbol of the preamble sequence transmission. Thelength of the window in number of slots, based on the subcarrier spacingfor Type0-PDCCH common search space is provided by higher layerparameter rar-WindowLength.

If a UE detects the PDCCH with the corresponding RA-RNTI and acorresponding PDSCH that includes a DL-SCH transport block within thewindow, the UE passes the transport block to higher layers. The higherlayers parse the transport block for a random access preamble identity(RAPID) associated with the PRACH transmission. If the higher layersidentify the RAPID in RAR message(s) of the DL-SCH transport block, thehigher layers indicate an uplink grant to the physical layer. This isreferred to as random access response (RAR) UL grant in the physicallayer. If the higher layers do not identify the RAPID associated withthe PRACH transmission, the higher layers can indicate to the physicallayer to transmit a PRACH. A minimum time between the last symbol of thePDSCH reception and the first symbol of the PRACH transmission is equalto N_(T,1)+Δ_(new)+0.5 msec where N_(T,1) is a time duration of N₁symbols corresponding to a PDSCH reception time for PDSCH processingcapability 1 when additional PDSCH DM-RS is configured and Δ_(new)≥0.

A UE shall receive the PDCCH with the corresponding RA-RNTI and thecorresponding PDSCH that includes the DL-SCH transport block with thesame DM-RS antenna port quasi co-location properties, as for a detectedSS/PBCH block or a received CSI-RS. If the UE attempts to detect thePDCCH with the corresponding RA-RNTI in response to a PRACH transmissioninitiated by a PDCCH order, the UE assumes that the PDCCH and the PDCCHorder have same DM-RS antenna port quasi co-location properties.

A RAR UL grant schedules a PUSCH transmission from the UE (Msg3 PUSCH).The contents of the RAR UL grant, starting with the MSB and ending withthe LSB, are given in Table 7. Table 7 shows random access responsegrant content field size.

TABLE 7 Number of RAR grant field bits Frequency hopping flag 1 Msg3PUSCH frequency resource allocation 12 Msg3 PUSCH time resourceallocation 4 MCS 4 TPC command for Msg3 PUSCH 3 CSI request 1 Reservedbits 3

The Msg3 PUSCH frequency resource allocation is for uplink resourceallocation type 1. In case of frequency hopping, based on the indicationof the frequency hopping flag field, the first one or two bits,N_(UL,hop) bits, of the Msg3 PUSCH frequency resource allocation fieldare used as hopping information bits as described in following [TableI.5].

The MCS is determined from the first sixteen indices of the applicableMCS index table for PUSCH.

The TPC command δ_(msg2,b,f,c) is used for setting the power of the Msg3PUSCH, and is interpreted according to Table 8. Table 8 shows TPCcommand δ_(msg2,b,f,c) for Msg3 PUSCH.

TABLE 8 TPC command Value(in dB) 0 −6 1 −4 2 −2 3 0 4 2 5 4 6 6 7 8

In non-contention based random access procedure, the CSI request fieldis interpreted to determine whether an aperiodic CSI report is includedin the corresponding PUSCH transmission. In contention based randomaccess procedure, the CSI request field is reserved.

Unless a UE is configured a subcarrier spacing, the UE receivessubsequent PDSCH using same subcarrier spacing as for the PDSCHreception providing the RAR message.

If a UE does not detect the PDCCH with a corresponding RA-RNTI and acorresponding DL-SCH transport block within the window, the UE performsthe procedure for random access response reception failure.

For example, the UE may perform power ramping for retransmission of theRandom Access Preamble based on a power ramping counter. However, thepower ramping counter remains unchanged if a UE conducts beam switchingin the PRACH retransmissions as shown in FIG. 12 .

FIG. 12 is a diagram for explaining a ramping counter of a PRACH.

In FIG. 12 , the UE may increase the power ramping counter by 1, whenthe UE retransmit the random access preamble for the same beam. However,when the beam had been changed, the power ramping counter remainsunchanged.

Regarding Msg3 PUSCH transmission, higher layer parameter msg3-tpindicates to a UE whether or not the UE shall apply transform precoding,for an Msg3 PUSCH transmission. If the UE applies transform precoding toan Msg3 PUSCH transmission with frequency hopping, the frequency offsetfor the second hop is given in Table 9. Table 9 shows frequency offsetfor second hop for Msg3 PUSCH transmission with frequency hopping.

TABLE 9 Number of PRBs in Value of V_(UL, hop) Frequency offset forinitial active UL BWP Hopping Bits 2^(nd) hop N_(BWP) ^(size) < 50 0N_(BWP) ^(size)/2 1 N_(BWP) ^(size)/4 N_(BWP) ^(size) > 50 00 N_(BWP)^(size)/2 01 N_(BWP) ^(size)/4 10 −N_(BWP) ^(size)/4 11 reserved

The subcarrier spacing for Msg3 PUSCH transmission is provided by higherlayer parameter msg3-scs. A UE shall transmit PRACH and Msg3 PUSCH on asame uplink carrier of the same serving cell. An UL BWP for Msg3 PUSCHtransmission is indicated by SystemInformationBlockType1.

A minimum time between the last symbol of a PDSCH reception conveying aRAR and the first symbol of a corresponding Msg3 PUSCH transmissionscheduled by the RAR in the PDSCH for a UE when the PDSCH and the PUSCHhave a same subcarrier spacing is equal toN_(T,1)+N_(T,2)+N_(TA,max)+0.5 msec. N_(T,1) is a time duration of N₁symbols corresponding to a PDSCH reception time for PDSCH processingcapability 1 when additional PDSCH DM-RS is configured, N_(T,2) is atime duration of N₂ symbols corresponding to a PUSCH preparation timefor PUSCH processing capability 1, and N_(TA,max) is the maximum timingadjustment value that can be provided by the TA command field in theRAR.

In response to an Msg3 PUSCH transmission when a UE has not beenprovided with a C-RNTI, the UE attempts to detect a PDCCH with acorresponding TC-RNTI scheduling a PDSCH that includes a UE contentionresolution identity. In response to the PDSCH reception with the UEcontention resolution identity, the UE transmits HARQ-ACK information ina PUCCH. A minimum time between the last symbol of the PDSCH receptionand the first symbol of the corresponding HARQ-ACK transmission is equalto N_(T,1)+0.5 msec. N_(T,1) is a time duration of N₁ symbolscorresponding to a PDSCH reception time for PDSCH processing capability1 when additional PDSCH DM-RS is configured.

Beam Failure Recovery (BFR)

In performing a DL/UL beam management process, a beam mismatch problemmay occur depending on configured periodicity of beam management. Inparticular, if a radio channel environment is changed because a UE movesits location or rotates or due to a movement of a surrounding object(e.g., an LoS environment is changed into a non-LoS environment becausea beam is blocked), an optimum DL/UL beam pair may be changed. Ingeneral, such a change may be said that a beam failure event hasoccurred when tracking fails in a beam management process performed bynetwork indication. A UE may determine whether such a beam failure eventoccurs through reception quality of a downlink RS. A report message forsuch a situation or a message (called a beam failure recovery request(BFRQ) message) for a beam recovery request needs to be delivered from aUE. A base station that has received such a message may perform beamrecovery through various processes, such as beam RS transmission or abeam reporting request for the beam recovery. Such a series of beamrecovery process is called beam failure recovery (BFR). In Rel-15 NR, abeam failure recovery (BFR) process for a PCell or a PScell (both arespecial cells (also called an SpCell)) in which a contention based PRACHresource is always present has been standardized. The correspondingprocedure is an operation within a serving cell, is configured asfollows as a beam failure detection (BFD) process of a UE, a BFRQprocess, and a process of monitoring, by a UE, a response of a basestation to a BFRQ (Reference: 3GPP TS38.213, TS38.321, TS38.331).

Beam Failure Detection (BFD)

If all PDCCH beams have a predetermined quality value (Q_out) or less,it is said that one beam failure instance has occurred (in this case,the quality is based on a hypothetical block error rate (BLER): That is,assuming that control information has been transmitted in acorresponding PDCCH, the probability that the demodulation ofcorresponding information will fail.

In this case, one or a plurality of search spaces in which a PDCCH willbe monitored may be configured in a UE. All the PDCCH beams may bedifferently configured for each search space. In this case, this meansthat all the beams have a BLER threshold or less. The following twomethods are supported as a criterion for determining, by a UE, a BFD RS.

[Implicit configuration of BFD RSs] a control resource set (refer toCORESET [TS38.213, TS38.214, TS38.331]) ID, that is, a resource regionin which a PDCCH may be transmitted is configured in each search space.QCLed RS information (e.g., CSI-RS resource ID, SSB ID) from a spatialRX parameter viewpoint may be indicated/configured for each CORESET ID(in the NR standard, a QCLed RS is indicated/configured through transmitconfiguration information indication). In this case, the QCLed RS (i.e.,QCL Type D in TS38.214) from the spatial RX parameter viewpoint meansthat a method of notifying, by a base station, a UE that the UE has touse (or may use) a beam used in corresponding spatially QCLed RSreception in corresponding PDCCH DMRS reception. As a result, from abase station viewpoint, this method is a method of notifying a UE thatthe UE has to perform transmission by applying the same transmissionbeam or a similar transmission beam (e.g., when beam directions are thesame/similar, but beam widths are different) between spatially QCLedantenna ports.

[Explicit configuration of BFD RSs] a base station may explicitlyconfigure a beam RS(s) for the use (beam failure detection). In thiscase, a corresponding beam RS(s) corresponds to the ‘all PDCCH beam’.

Whenever an event in which a hypothetical BLER measured based on a BFDRS(s) in a UE physical layer is deteriorate to a specific threshold ormore occurs, what beam failure instance (BFI) has occurred is notifiedthrough a MAC sublayer. When a BFI occurs as much as a given number(beamFailureInstanceMaxCount) within a given time (BFD timer), a UE MACsublayer determines that a beam failure has occurred and initiates arelated RACH operation.

Hereinafter, a MAC layer operation related to BFD is described.

MAC entity:

-   -   1> when beam failure instance indication is received in lower        layers:    -   2> starts or starts again beamFailureDetectionTimer.    -   2> increases BFI_COUNTER by 1.    -   2> when BFI_COUNTER>=beamFailureInstanceMaxCount:    -   3> initiate a random access procedure in a SpCell.    -   1> when beamFailureDetectionTimer expires; or    -   1> when beamFailureDetectionTimer, beamFailureInstanceMaxCount        or a reference signal (any of the reference signals used for        beam failure detection) used to detect a beam failure is        reconfigured by a higher layer:    -   2> configures BFI_COUNTER to 0.    -   1> when a random access procedure is successfully completed:    -   2> configures BFI_COUNTER to 0.    -   2> stops (configured) beamFailureRecoveryTimer.    -   2> considers that the beam failure recovery procedure has been        successfully completed.

BFRQ (Based on PRACH): New Beam Identification+PRACH Transmission

As described above, when a specific number of BFIs or more occur, a UEmay determine that a beam failure has occurred, and may perform a beamfailure recovery operation. As an example of the beam failure recoveryoperation, a beam failure recovery request (BFRQ) operation based on aRACH procedure (i.e., PRACH) may be performed. Hereinafter, acorresponding BFRQ procedure is specifically described.

When a BF occurs in a corresponding UE, a base station may configure anRS list (candidateBeamRSList) corresponding to candidate beams which maybe replaced as RRC. Dedicated PRACH resources may be configured forcorresponding candidate beams. In this case, the dedicated PRACHresources are non-contention based PRACH (also called contention freePRACH) resources. If a beam is not found in the corresponding list, abeam is selected among pre-configured SSB resources and a contentionbased PRACH is transmitted. A detailed procedure is as follows.

Step 1) a UE finds a beam having a predetermined quality value (Q_in) ormore among RSs configured as a candidate beam RS set by a base station.

If one beam RS is greater than a threshold, a corresponding beam RS isselected.

If a plurality of beam RSs is greater than a threshold, given one of thecorresponding beam RSs is selected

If a beam greater than a threshold is not present, Step 2 is performed.

Note1: In this case, beam quality is based on RSRP.

Note2: the RS beam set configured by the base station includes threecases.

-   -   1) All beam RSs within the RS beam set are configured as SSBs    -   2) All beam RSs within the RS beam set are configured as CSI-RS        resources    -   3) Beam RSs within the RS beam set are configured as SSBs and        CSI-RS resources

Step 2) A UE finds a beam having a predetermined quality value (Q_in) ormore among SSBs (related to a contention based PRACH resource)

If one SSB is greater than a threshold, a corresponding beam RS isselected.

If a plurality of SSB is greater than a threshold, given one ofcorresponding beam RSs is selected.

If a beam greater than a threshold is not present, Step 3 is performed.

Step 3) A UE selects a given SSB among SSBs (connected to a contentionbased PRACH resource)

The UE transmits, to a base station, a PRACH resource & preamble thathas been connection configured directly or indirectly to the beam RS(CSI-RS or SSB) selected in the above process.

In this case, the direct connection configuration is used in the case ofthe following 1) or 2).

-   -   1) If a contention-free PRACH resource & preamble is configured        for a specific RS with respect to a candidate beam RS set        separately configured for BFR use,    -   2) If a (contention based) PRACH resource & preamble mapped to        SSBs generally configured for other use, such as random access,        in a one-to-one manner

In this case, the indirect connection configuration is used in thefollowing cases.

If a contention-free PRACH resource & preamble is not configured for aspecific CSI-RS within a candidate beam RS set separately configured forBFR use.

In this case, a UE selects a (contention-free) PRACH resource & preambleconnected to SSB designed to be received through the same reception beamas a corresponding CSI-RS (i.e., quasi-co-located (QCLed) with respectto spatial Rx parameter).

Monitoring of gNB's Response to the BFRQ

A UE monitors the replay of a base station (gNB) for corresponding PRACHtransmission.

In this case, a response to a contention-free PRACH resource & preambleis transmitted in a PDCCH masked with a C-RNTI, and is separatelyreceived in a RRC-configured search space for BFR.

The search space is configured in a specific CORESET (for BFR).

A CORESET (e.g., CORESET 0 or CORESET 1) and search space configured fora common contention PRACH based random access process is used for aresponse to a contention PRACH without any change.

If a reply is not present for a given time, the UE repeats a new beamidentification & selection process and a BFRQ & monitoring gNB'sresponse process.

The process may be performed until PRACH transmission reaches a presetmaximum number N_max or a configured timer (BFR timer) expires.

When the timer expires, the UE stops contention free PRACH transmission,but may perform contention based PRACH transmission based on theselection of an SSB until N_max is reached.

FIG. 13 is a diagram for describing a beam failure recovery-relatedoperation to which a method proposed in the present disclosure may beapplied. Specifically, FIG. 13 illustrates a beam failure recoveryoperation in a primary cell (PCell).

Scheduling Request

A scheduling request (SR) is used to request an UL-SCH resource for newtransmission.

0, 1 or one or more SR configurations may be configured in the MACentity. The SR configuration is configured as a series of PUCCHresources for an SR in different BWPs and cells. In the case of alogical channel, a maximum of one PUCCH resource is configured for an SRper BWP.

Each SR configuration corresponds to one or more logical channels. Eachlogical channel may be mapped to 0 or one SR configuration configured byRRC. An SR configuration of a logical channel that has triggered a BSR(when such a configuration is present) is considered as a correspondingSR configuration for a triggered SR.

RRC configures the following parameters for a receiving schedulingrequest procedure.

-   -   SR-Prohi bitTimer (per SR configuration)    -   sr-TransMax (per SR configuration).

The following UE variables are used for the scheduling requestprocedure.

-   -   SR_COUNTER (per SR configuration).

If an SR is triggered and other pending SRs corresponding to the same SRconfiguration are not present, the MAC entity needs to configureSR_COUNTER of a corresponding SR configuration to 0.

When an SR is triggered, it is considered that the SR is pending untilit is cancelled. All pending SRs triggered before a MAC PDU assembly arecancelled, and sr-Prohi bitTimer needs to be stopped until the MAC PDUis transmitted. The PDU includes a Long or Short BSR MAC CE including abuffer status up to the last event triggered before the MAC PDUassembly. When all pending data available for transmission in which ULgrant can be transmitted can be accommodated, all the pending SRs arecancelled, and each sr-Prohi bitTimer needs to be stopped.

It is considered that only PUCCH resources of a BWP activated in a timeof SR transmission occasion are valid.

One MAC entity in which one or more SRs are pending needs to perform thefollowing on each pending SR:

-   -   1> when a valid PUCCH resource configured for a pending SR is        not present in the MAC entity:    -   2> an SpCell starts a random access procedure and cancels a        pending SR.    -   1> If not, in the case of an SR configuration corresponding to a        pending SR:    -   2> An MAC entity has an SR transmission occasion on valid PUCCH        resource for a configured SR;    -   2> in a time of SR transmission occasion, sr-Prohi bitTimer is        not executed;    -   2> a PUCCH resource for an SR transmission occasion does not        overlap a measurement gap;    -   2> When a PUCCH resource for an SR transmission occasion does        not overlap an UL-SCH resource:    -   3> when SR_COUNTER<sr-TransMax:    -   4> SR_COUNTER is increased by 1.    -   4> a physical layer indicates that an SR is signaled on one        valid PUCCH resource for an SR;    -   4> sr-Prohi bitTimer is started.    -   3> In other cases:    -   4> the release of a PUCCH for all serving cells is notified        through RRC;    -   4> the release of an SRS for all serving cells is notified        through RRC;    -   4> configured downlink assignment and an uplink grant are        released.    -   4> all PUSCH resources for semistatic CSI report are cleared.    -   4> an SpCell starts a random access procedure and cancels all        pending SRs.

Reference 1: when an MAC entity has more than one overlapping validPUCCH resources for an SR transmission occasion, the selection of avalid PUCCH resource for an SR for signaling the SR depends on a UEimplementation.

Reference 2: when two or more individual SRs triggers a commandinstructing that an SR should be signals in the same valid PUCCHresource from a MAC entity to a PHY layer, SR_COUNTER for a relevant SRconfiguration is increased once.

The MAC entity may stop a random access procedure in progress (initiatedby the MAC entity before a MAC PDU assembly) due to a pending SR inwhich a valid PUCCH resource is not configuration. Such a random accessprocedure may be stopped until a MAC PDU is transmitted by using an ULgrant other than an UL grant provided by a random access response. ThePDU includes a buffer status until the last event at which a BSR istriggered before the MAC PDU assembly or when an UL grant(s) canaccommodate all pending data available for transmission.

PUCCH Formats

PUCCH formats may be classified depending on symbol duration, a payloadsize, and multiplexing. Table 10 indicates corresponding PUCCH formats.

TABLE 10 Length in OFDM PUCCH symbols Number format N_(symb) ^(PUCCH) ofbits Usage Etc 0 1-2  ≤2 HARQ, SR Sequence selection 1 4-14 ≤2 HARQ,[SR] Sequence modulation 2 1-2  >2 HARQ, CSI, CP-OFDM [SR] 3 4-14 >2HARQ, CSI, DFT-s-OFDM [SR] (no UE multiplexing) 4 4-14 >2 HARQ, CSI,DFT-s-OFDM [SR] (Pre DFT OCC)

Short-Duration PUCCH

A short-duration PUCCH may be divided into Formats 0 and 2. A shortPUCCH having 2 symbols may be configured as one symbol short PUCCHstructure is repeated.

The PUCCH Format 0 may support UCI having a maximum of 2 bits along withmultiplexing. The Format 0 may be used when Low latency support, UCIhaving a small size, or a low PAPR is necessary. The Format 0 has astructure based on sequence (cyclic shift, CS) selection without a DMRS,and may generate 1 PRB or 1 to 2 symbols. Furthermore, the Format 0 maysupport a maximum of 3 UEs (in the case of 2 bits) or 6 UEs (in the caseof 1 bit) per PRB.

The PUCCH Format 2 may support UCI having two bits or more withoutmultiplexing. The PUCCH Format 2 may be used for Low latency support,UCI having a middle or large size. The PUCCH Format 2 may occupy 1 to 16PRBs or 1 to 2 symbols. Furthermore, the PUCCH Format 2 may support oneUE per PRB without multiplexing.

Long-Duration PUCCH

A PUCCH Format 1 may support UCI having a maximum of 2 bits along withmultiplexing. The PUCCH Format 1 may be applied to coverage support, UCIhaving a small size, and many multiplexing. The PUCCH Format 1 has anLTE PF1-like structure (a structure in which an OCC and DMRS/UCI symbolof a time domain are intersected). The PUCCH Format 1 may occupy 1 PRB,4 to 14 symbols, and may support a maximum of 84 UEs (12CSs×7 OCCs) perPRB.

A PUCCH Format 3 may support UCI having two bits or more withoutmultiplexing. The PUCCH Format 3 may be applied to coverage support, UCIhaving a large size. The PUCCH Format 3 may occupy 1 to 16 PRBs, 4 to 14symbols. The PUCCH Format 3 may support one UE per PRB withoutmultiplexing.

A PUCCH Format 4 may support UCI having two bits or more along withmultiplexing. The PUCCH Format 4 may be used for coverage support, UCIhaving a middle size. The PUCCH Format 4 has an LTE PF5-like structure(TDM of DMRS and DFTed UCI with F-domain OCC). The PUCCH Format 4 mayoccupy 1 PRB, 4 to 14 symbols, and may support a maximum of 2 UEs (whenSF=2) or a maximum of 4 UEs (when SF=4) per PRB.

In Relation to UCI Multiplexing

When an overlap between a PUCCH(s)/PUSCH(s) occurs, multiplexing (i.e.,UCI multiplexing) for UCI may be performed. The UCI multiplexing may bedenoted as a PUCCH merging method. The UCI multiplexing may beconfigured as a procedure of Step 2.

In Step 1, a set of (in the time) not overlapped PUCCH resource(s) forUCI multiplexing may be determined (regardless of whether a PUSCH(s) ispresent) by merging a set of overlapping PUCCH resources.

Specifically, in Step 1, while PUCCH resource overlaps in a slot, aPUCCH resource (resource A) overlapping another PUCCH resource havingthe fastest start (and a maximum duration) may be determined. A PUCCHresource set (set X) overlapping the resource A may be determined. OnePUCCH resource for multiplexing UCI of the resource A and the PUCCHresource of the set X may be determined. The set X (including theresource A) may be replaced with the determined PUCCH resource.

In Step 2, when a PUCCH resource(s) overlaps a PUSCH(s) as a result inStep 1, pieces of UCI are multiplexed on the overlapped PUSCH. If not,pieces of UCI may be multiplexed on the determined PUCCH resource.

UCI Multiplexing on PUCCH

UE Procedure for reporting HARQ-ACK and an SR

-   -   ACKNACK PUCCH format 0+SR PUCCH format 0/1: in the case of a        positive SR, HARQ-ACK may be transmitted in an AN PR0 along with        an additional CS offset. In the case of a negative SR, HARQ-ACK        may be transmitted in an ACKNACK PUCCH format 0 without an        additional CS offset.    -   ACKNACK PUCCH format 1+SR PUCCH format 0: (an SR is dropped)        only HARQ-ACK may be transmitted in the ACKNACK PUCCH format 1.    -   ACKNACK PUCCH format 1+SR PUCCH format 1: in the case of a        positive SR, HARQ-ACK may be transmitted through a        (corresponding) SR PUCCH format 1 resource. In the case of a        negative SR, HARQ-ACK may be transmitted through an ACKNACK        PUCCH format 1 resource.    -   ACKNACK PUCCH format 2/3/4+SR PUCCH format 0/1: In the case of        configured K SR PUCCHs, UCI in which ceil (log 2 (K+1)) bits        indicating (all) negative or positive SR (ID) are added and        combined with HARQ-ACK bits may be transmitted in the ACKNACK        PUCCH format 2/3/4 resource.

Table 11 illustrates an example of a pre-configured rule/method relatedto multiplexing (i.e., PUCCH merging) between an ACKNACK PUCCH formatand an SR PUCCH format (e.g., 3GPP TS 38.213. section 9.2.5 Reference).

TABLE 11 If a UE would transmit a PUCCH with O_(ACK) HARQ-ACKinformation bits in a resource using PUCCH format 2 or PUCCH format 3 orPUCCH format 4 in a slot, as described in Subclause 9.2.3, ┌log₂(K + 1)┐bits representing a negative or positive SR, in ascending order of thevalues of schedulingRequestResourceId, are appended to the HARQ-ACKinformation bits and the UE transmits the combined O_(UCI) = O_(ACK) +┌log₂(K + 1)┐ UCI bits in a PUCCH using a resource with PUCCH format 2or PUCCH format 3 or PUCCH format 4 that the UE determines as describedin Subclauses 9.2.1 and 9.2.3. An all-zero value for the ┌log₂(K + 1)┐bits represents a negative SR value across all K SRs.

UE procedure for CSI and an SR report

-   -   CSI PUCCH format 2/3/4+SR PUCCH format 0/1: in the case of a        configured K SR PUCCH, UCI in which ceil (log 2 (K+1)) bits        indicating (all) negative or positive SR (ID) are added and        combined with CSI feedback bits may be transmitted in the CSI        PUCCH format 2/3/4 resource.

Table 12 illustrates an example of a pre-configured rule/method relatedto multiplexing between a CSI PUCCH format and an SR PUCCH format (i.e.,PUCCH merging) (e.g., 3GPP TS 38.213. section 9.2.5 Reference).

TABLE 12 If a UE would transmit a PUCCH with O_(CSI) CSI report bits ina resource using PUCCH format 2 or PUCCH format 3 or PUCCH format 4 in aslot, ┌log₂(K + 1)┐ bits representing corresponding negative or positiveSR, in ascending order of the values of schedulingRequestResourceId, areprepended to the CSI information bits as described in Subclause 9.2.5.2and the UE transmits a PUCCH with the combined O_(UCI) = ┌log₂(K + 1)┐ +O_(CSI) UCI bits in a resource using the PUCCH format 2 or PUCCH format3 or PUCCH format 4 for CSI reporting. An all-zero value for the┌log₂(K + 1)┐ bits represents a negative SR value across all K SRs.

UE Procedure for Reporting HARQ-ACK/SR and CSI when a PUCCH ResourceIndicator (PRI) is Indicated

-   -   HARQ-ACK/SR and CSI may be transmitted through a PUCCH resource.        One PUCCH resource set may be selected from several sets based        on a total of UCI payloadsize        N_(UCI)=(O_(ACK)+O_(SR)+O_(CSI)+O_(CRC)). A PUCCH resource        within the selected set may be indicated by a PRI signaled in DL        scheduling DCI. Furthermore, the number of PRBs (actually used)        in a PUCCH resource may be determined based on a total UCI size        NUCI and a maximum of coding rate R configured based on a PUCCH        format. A minimum number of PRBs which may transmit the total        UCI size NUCI along the coding rate R may be selected.

UE Procedure for Reporting HARQ-ACK/SR and CSI if PRI is not Indicated

-   -   HARQ-ACK/SR and CSI may be transmitted through a CSI PUCCH        resource. A PUCCH resource may be selected from multiple CSI        PUCCH resources based on a total UCI payload size NUCI and a        maximum coding rate R. A resource capable of delivering a        minimum UCI capacity (e.g., {# of Res}×R) and the total UCI size        NUCI may be selected. The number of PRBs (actually used) in a        PUCCH resource may be determined based on the total UCI size        NUCI and the maximum coding rate R.

UCI Multiplexing on a PUCCH According to Coupling Between an ACKNACKPUCCH Format and a CSI PUCCH Format

Table 13 illustrates an example of UCI multiplexing on a PUCCH accordingto coupling between an ACKNACK PUCCH format and a CSI PUCCH format. In aPUCCH, in the case of a Part2 CSI report, a PUCCH resource and multiplePRBs for the corresponding PUCCH resource may be determined based on aUCI payload size assuming that a CSI report is rank 1.

TABLE 13 PUCCH-Format3/4- PUCCH-Format2-simultaneous-simultaneous-HARQ-ACK-CSI = HARQ-ACK-CSI = True/ True/ Determinedresource with Determined resource with ACKNACK/SR + CSI is FormatACKNACK/SR + CSI is Format 2 3/4 CSI configured Jointly encode ACKNACKand Jointly encode ACKNACK and with Format 2 CSI report CSI report CSIconfigured Jointly encode ACKNACK and Jointly encode ACKNACK and withFormat CSI Part 1. CSI Part 1 at the configured max 3/4 Drop CSI Part 2.code rate. Separately encode CSI Part 2 using the remaining resources(if any) in the PUCCH

Physical Uplink Control Channel (PUCCH)

A PUCCH supports multiple formats. The PUCCH formats may be classifiedbased on symbol duration, a payload size and multiplexing. Table 14 is atable illustrating an example of the PUCCH formats.

TABLE 14 PUCCH length in OFDM Number of Format symbols bits Usage Others0 1-2  ≤2 1 sequence selection 1 4-14 ≤2 2 sequence modulation 2 1-2  >24 CP-OFDM 3 4-14 >2 8 DFT-s-OFDM (no UE multiplexing) 4 4-14 >2 16DFT-s-OFDM (Pre DFT OCC)

The PUCCH formats in Table 14 may be basically divided into (1) a shortPUCCH and (2) a long PUCCH. The PUCCH formats 0 and 2 may be included inthe short PUCCH, and the PUCCH formats 1, 3 and 4 may be included in thelong PUCCH.

A UE transmits one or two PUCCHs through a serving cell in differentsymbols within one slot. If two PUCCHs are transmitted in one slot, atleast one of the two PUCCHs has a structure having a short PUCCH. Thatis, in one slot, (1) the transmission of a short PUCCH and a short PUCCHis possible and (2) the transmission of a long PUCCH and a short PUCCHis possible, but (3) the transmission of a long PUCCH and a long PUCCHis impossible.

The aforementioned contents (the 3GPP system, the frame structure, andthe NR system) may be combined with methods to be described later, whichare proposed in the present disclosure, and may be applied or may besupplemented in order to clarify a technical characteristic of themethods proposed in the present disclosure. The methods describedhereinafter are classified merely for convenience of description, andsome elements of any one method may be substituted with some elements ofanother method or may be mutually combined and applied.

In the present disclosure, a background of a BFRQ for an SCell and amethod of effectively processing a beam failure occurring in a pluralityof SCells are described.

In relation to the application of the aforementioned PRACH-based BFRprocedure, the following contents may be considered. In the case of aPRACH-based BFR procedure to which a carrier aggregation (CA) isapplied, an SCell may not have an UL carrier. Although an SCell has anUL carrier, it has technical limits in that a contention based PRACHcannot be configured. Accordingly, a PRACH-based BFR procedure to whicha carrier aggregation (CA) is applied is limitedly applied to only aPCell or a PSCell.

Due to limits in the application of the aforementioned PRACH-based BFRprocedure, the following problems occur. If a PCell is operated in a lowfrequency band (e.g., 6 GHz or less) and a high frequency band (e.g., 30GHz) is to be operated as an SCell, there is a problem in that a BFR isnot supported in the high frequency band in which BFR support is moreimportantly affected.

For the above reason, in Rel-16 NR MIMO work item, standardization for aBFR report for a secondary cell (SCell) is in progress. Accordingly, thefollowing contents may be considered.

UL transmission is impossible in a corresponding SCell with respect toat least DL only SCell. Accordingly, a (dedicated) PUCCH resource(s)used when a base station is notified that a beam failure has occurred ina corresponding SCell may be configured in a special cell (SpCell). Abeam failure recovery request (BFRQ) for the SCell may be performedbased on the configured PUCCH resources.

Hereinafter, a PUCCH configured for the beam failure recovery of anSCell is referred to as a FR-PUCCH for convenience of description. Theterm is used to distinguish between the term and another PUCCH inhelping understanding, and is not intended to limit the technical scopethrough the corresponding term.

A role of a BFR-PRACH is to transmit both ‘the occurrence of a beamfailure+new beam RS (set) information’ to a base station.

In contrast, a role of a BFR-PUCCH is to notify a base station of only‘the occurrence of a beam failure for an SCell(s)’. Detailed informationrelated to an occurred beam failure may be transmitted as a subsequentreport.

For example, a UE may transmit, to a base station, a MAC CE (or UCI)including information for at least one of the following i) to iii) asthe subsequent report.

-   -   i) An SCell(s) in which a beam failure has occurred example: CC        index(s)    -   ii) whether a new beam for an SCell(s) in which a beam failure        has occurred is present    -   iii) a corresponding beam RS ID(+quality) when a new beam is        present

In the case of the iii), information for quality (RSRP or SINR) of a newbeam(s) according to a beam RS ID(s) may be included.

A subsequent beam report does not need to be always triggered.Specifically, after receiving a BFR-PUCCH, a base station may deactivatean SCell(s) in which a BFR configuration has been configured for acorresponding UE.

The above operation is for increasing UL resource utilization.Specifically, there is a case where several tens of SCells are connectedto one PCell/PSCell, and there may be many UEs sharing one PCell/PSCellUL from a base station viewpoint. When even such a case is considered,it is preferred that the amount of UL resources reserved in each UE asSCell BFRQ use is minimized in a PCell/PSCell. Accordingly, afterreceiving a BFR-PUCCH, the base station may deactivate an SCell(s) inwhich a beam failure has occurred.

A scheduling request (SR) PUCCH method may be reused in that the amountof information to be contained in a BFR-PUCCH is very small (e.g., 1bit) and a corresponding BFR-PUCCH is transmitted only when an event ofa UE occurs.

For example, when a BFR-PUCCH resource(s) is configured in PCell/PScellUL through a RRC message, the corresponding PUCCH resource(s) may beconfigured through only the PUCCH format 0 or the PUCCH format 1. Theexisting SR-related MAC sublayer operations, such as SR retransmissionor an SR prohibit timer, may be reused. Corresponding BFRQ informationmay be transmitted through another PUCCH resource or PUSCH resourceaccording to a collision handling rule and/or UCI multiplexing rule witha BFR-PUCCH and another PUCCH or PUSCH. In this case, the correspondingBFR-PUCCH resource(s) does not causes resource waste because theresource(s) is not a PUCCH resource always reserved from a base stationviewpoint.

Even in a MAC sublayer-related operation viewpoint, the followingembodiments may be considered.

For example, values in which an SR retransmission-related prohibit timervalue, a maximum retransmission value, etc. will be applied to a BFRQoperation and values to be applied to a common scheduling request may bedefined to be identically applied. For another example, in order for aBFRQ to be handled a urgent/important information compared to an SR, thevalues to be applied may be separately configured/defined with respectto the SR and BFRQ.

In particular, a base station that has received a BFRQ may deactivate acorresponding Scell(s) without performing beam recovery on an SCell(s)of a corresponding UE. In such a case, it will be unnecessary for thebase station to retransmit the BFRQ several times because the basestation will not allocate an UL-SCH to the UE. By considering this, amaximum retransmission value for the BFRQ may be smallerconfigured/defined. For example, the BFRQ may not be retransmitted (amaximum retransmission value=1).

If a BFR-PUCCH resource and an SR-PUCCH resource (for a specificBWP/serving cell) are (temporally) overlapped and configured and anevent that an SR-related pre-defined event and BFRQ (for a correspondingBWP/serving cell) needs to be transmitted occurs, there is a problem inthat ambiguity occurs regarding how a UE transmits which one of PUCCHresources configured for an SR use and PUCCH resources configured for aBFRQ use. The present disclosure proposes the following methods (e.g.,Method 1(Method 1.1/1.2)/Method 2/Method 3/Method 4) of Proposal 1 as asolution thereto.

[Proposal 1]

If a BFR-PUCCH resource and an SR-PUCCH resource are overlapped and ascheduling request event (SR event) and a beam failure event (BF event)occur together, a UE/base station may operate according to Method1(Method 1.1/1.2)/Method 2/Method 3/Method 4 to be described later.

[Method 1]

A UE may select a BFR-PUCCH resource and first transmit a BFRQ.

[Method 1.1]

A UE may stop (pend) an SR procedure, and may transmit an SR-PUCCHthrough a valid SR-PUCCH resource after BFRQ transmission.

[Method 1.2]

A UE may cancel a pending SR by considering a situation for a no validPUCCH resource for an SR with respect to the SR, and may initiate arandom access procedure.

Method 1 is a method giving priority to recovery of a beam.

Specifically, when an SR event and a BFR event as a case where anSR-PUCCH resource and a BFR-PUCCH resource are overlapped simultaneouslyoccur, in Method 1, a UE selects and reports the BFR-PUCCH resourcebecause the recovery of a beam is first. Effects according to Method 1are as follows. A base station can more preferentially recognize a BFRsituation than an SR-related situation with respect to a correspondingUE. A base station can preferentially perform a determination, such asthat a beam recovery procedure is performed or a corresponding Scell(s)is deactivated.

If Method 1.1 is applied, when SR transmission/retransmission iscontrolled, an SR procedure may be changed so that the method islimitedly applied to a case where a collision against a BFRQ resource isnot present. Table 15 is an embodiment of a MAC layer operationviewpoint related to the application of Method 1.1.

TABLE 15 1> If a valid PUCCH resource configured for a pending SR is notpresent in a MAC entity: 2> An SpCell starts a random access procedure(a random access-related procedure Reference) and cancels the pendingSR. 1> If not, with respect to an SR configuration corresponding to thepending SR: 2> When an MAC entity has an SR transmission occasion on avalid PUCCH resource for a configured SR; 2> if sr-ProhibitTimer is notexecuted in a time of the SR transmission occasion; 2> a PUCCH resourcefor the SR transmission occasion does not overlap a measurement gap; 2>a PUCCH resource for the SR transmission occasion does not overlap anUL-SCH resource; 2> a PUCCH resource for the SR transmission occasiondoes not overlap a PUCCH resource for a BFRQ: 3> when SR_COUNTER <sr-TransMax: 4> SR_COUNTER is increased by 1; 4> a physical layerindicates that an SR is signaled on one valid PUCCH resource for the SR;4> sr-ProhibitTimer is started. 3> In other cases: 4> Notification isprovided so that a PUCCH for all serving cells is released through RRC;4> Notification is provided so that an SRS for all serving cells isreleased through RRC; 4> Configured downlink assignment and an uplinkgrant are cleared. 4> All PUSCH resources for a semi-permanent CSIreport are cleared. 4> An SpCell starts a random access procedure andcancels pending all SRs. Reference 1: when a MAC entity has more thanone overlapping valid PUCCH resource for an SR transmission occasion,the selection of a valid PUCCH resource for an SR for signaling the SRdepends on a UE implementation. Reference 2: when two or more individualSRs trigger a command to signal the SRs in the same valid PUCCH resourcefrom the MAC entity to the PHY layer, SR_COUNTER for a relevant SRconfiguration is increased only once

Furthermore, Method 1.2 is a method of operating an RS as a fall-backprocedure (an underlined portion in Table 16). If the method is applied,the contents of Reference 3 in Table 16 may be applied to an operationof a UE/base station.

TABLE 16 1> If a valid PUCCH resource configured for a pending SR is notpresent in a MAC entity: 2> An SpCell starts a random access procedure(a random access-related procedure Reference) and cancels the pendingSR. 1> If not, with respect to an SR configuration corresponding to thepending SR: 2> When an MAC entity has an SR transmission occasion on avalid PUCCH resource for a configured SR; 2> if sr-Prohi bitTimer is notexecuted in a time of the SR transmission occasion; 2> a PUCCH resourcefor the SR transmission occasion does not overlap a measurement gap; 2>a PUCCH resource for the SR transmission occasion does not overlap anUL-SCH resource; 2> a PUCCH resource for the SR transmission occasiondoes not overlap a PUCCH resource for a BFRQ: 3> when SR_COUNTER <sr-TransMax: 4> SR_COUNTER is increased by 1; 4> a physical layerindicates that an SR is signaled on one valid PUCCH resource for the SR;4> sr-ProhibitTimer is started. 3> In other cases: 4> Notification isprovided so that a PUCCH for all serving cells is released through RRC;4> Notification is provided so that an SRS for all serving cells isreleased through RRC; 4> Configured downlink assignment and an uplinkgrant are cleared. 4> All PUSCH resources for a semi-permanent CSIreport are cleared. 4> An SpCell starts a random access procedure andcancels pending all SRs. Reference 1: when a MAC entity has more thanone overlapping valid PUCCH resource for an SR transmission occasion,the selection of a valid PUCCH resource for an SR for signaling the SRdepends on a UE implementation. Reference 2: when two or more individualSRs trigger a command to signal the SRs in the same valid PUCCH resourcefrom the MAC entity to the PHY layer, SR_COUNTER for a relevant SRconfiguration is increased only once. Reference 3: when a PUCCH resourcefor an SR transmission occasion overlaps a PUCCH resource for the BFRQtranmission occasion, a PUCCH resource for the SR transmission occasionis considered to be invalid (or considered to be pending in the case ofMethod 1.1 and Method 1.3)

[Method 2]

A UE may select a PUCCH resource separately configured/regulated to beused upon simultaneous transmission of a BFRQ event and an SR event, andmay transmit an SR and BFRQ.

A base station may separately configure a PUCCH resource for BFRQ+SR inthe UE. Specifically, the base station may configure, in the UE, anSR-dedicated PUCCH resource(s), a BFRQ-dedicated PUCCH resource(s), anda PUCCH resource(s) for an SR+BFRQ use. The UE may select a separatelyconfigured PUCCH resource and transmit the SR and BFRQ (i.e., when an SRevent and a BFRQ event simultaneously occur) in the case of the SR+BFRQ.

[Method 3]

When a BFRQ/SR event occurs, a UE may transmit an SR/BFRQ in a specificPUCCH resource. Depending on whether an SR and BFRQ simultaneouslyoccur, the UE may transmit a separate sequence/message.

The separate sequence/message may have its state divided into thefollowing states depending on a format of the PUCCH resource and may berepresented.

-   -   1) A cyclic shift value of a sequence in the case of the PUCCH        format 0    -   2) A sequence in the case of the PUCCH format 1    -   3) UCI bits (on which channel coding will be performed) in the        case of the PUCCH format 2/3/4

Specifically, it may be defined that the following states are dividedand represented based on the 1) to 3).

-   -   {circle around (1)}positive SR+positive BFRQ or positive        SR+negative BFRQ (for SR-PUCCH)    -   {circle around (2)}positive BFRQ+positive SR or positive        BFRQ+negative SR (for BFR-PUCCH)    -   {circle around (3)}positive BFRQ+positive SR, positive        BFRQ+negative SR, negative BFRQ+positive SR, or negative        BFRQ+negative SR (for SR-PUCCH, BFR-PUCCH, or a PUCCH resource        used for both cases of SR and BFR)

The {circle around (1)} may be applied to an SR-PUCCH, the {circlearound (2)} may be applied to a BFR-PUCCH, and the {circle around (3)}may be applied to a PUCCH resource used when an SR-PUCCH/BFR-PUCCH/SRand a BFR simultaneously occur.

In Method 3, a UE transmits a BFR-PUCCH/SR-PUCCH through one of aBFR-PUCCH resource and an SR-PUCCH resource having a collision.Specifically, in Method 3, in the case of an SR+BFRQ situation, it isdefined/configured that a UE transmits a BFR-PUCCH/SR-PUCCH based onseparately defined/configured UCI bits, a sequence, or a sequence towhich a cyclic shift (CS) is applied depending on a PUCCH format.

For example, if a resource having the PUCCH format 0 is used for SRpurposes, HARQ-ACK/NACKinformation may be additionally transmitted basedon a CS value. The CS value may be differently defined/configureddepending on whether a BFRQ occurs with respect to a PUCCH resource foran SR purpose by using such a principle. In contrast, a PUCCH resourcefor a BFR purpose uses a resource having the PUCCH format 0, a UE maytransmit a corresponding PUCCH only in a BFR situation. In this case,information indicating whether an SR is positive (i.e., positive SR ornegative SR) may also be transmitted depending on the CS value. In thecase of the PUCCH format 1, the method may be applied by changing asequence not the CS value. Based on such a principle, an SR andBFRQ-combined use PUCCH resource may be configured. That is, one PUCCHresource may be configured to be used for an SR use and a BFRQ use. Forwhich use a corresponding PUCCH resource will be used may be reporteddepending on UCI transmitted through a corresponding PUCCH resource.Specifically, an SR use (SR event occurs), a BFRQ use (BFRQ eventoccurs) and/or an SR+BFRQ use (SR event and BFRQ event simultaneouslyoccur) may be reported through the UCI.

The BFR/SR-combined use PUCCH resource may be limitedly applied to acase where 1) a plurality of SCells sharing one PUCCH resource from aBFRQ viewpoint and 2) a plurality of Scells sharing one PUCCH resourcefrom an SR viewpoint are the same.

[Method 4]

A base station may configure an SR-PUCCH resource and a BFR-PUCCHresource to be always disposed at different symbols. Accordingly, a casewhere the SR-PUCCH resource and the BFR-PUCCH resource overlap can beprevented. A UE may not expect a configuration in which an SR-PUCCHresource and a BFR-PUCCH resource overlap.

Method 4 guarantees that an overlap between an SR-PUCCH resource and aBFR-PUCCH resource does not occur in resource allocation of a basestation. In this case, there is an advantage in that a UE does not needto perform special handling on a collision situation between an SR-PUCCHand a BFR-PUCCH, but a degree of freedom of a PUCCH resourceconfiguration of the base station may be limited. In particular, when acase where an SR PUCCH resource is configured every slot is considered,limitation inevitably occurs in symbol duration of an SR PUCCH resource.

From an implementation aspect, operations (e.g., the aforementionedproposal methods (e.g., operations related to beam failure recoverybased on at least one of Method 1/Method 1-1/Method 1-2/Method 2/Method3/Method 4 of Proposal 1)) of a base station/UE according to theaforementioned embodiments may be processed by the apparatus of FIGS. 17to 21 (e.g., the processor 102, 202 in FIG. 18 ) to be described later.

Furthermore, operations (e.g., operations related to beam failurerecovery based on at least one of Method 1/Method 1-1/Method 1-2/Method2/Method 3/Method 4 of Proposal 1) of a base station/UE according to anembodiment may be stored in a memory (e.g., 104, 204 in FIG. 18 ) in theform of an instruction/program (e.g., an instruction or an executablecode) for driving at least one processor (e.g., 102, 202 in FIG. 18 ).

FIG. 14 illustrates an example of signaling between a UE/base station towhich a method proposed in the present disclosure may be applied.Specifically, FIG. 14 illustrates an example of signaling between a userequipment (UE)/base station (BS) based on the aforementioned proposalmethod (e.g., Method 1/Method 1-1/Method 1-2/Method 2/Method 3/Method 4of Proposal 1). In this case, the UE/BS is merely an example, and may beapplied by being replaced with various apparatus as described in FIGS.17 to 21 . FIG. 14 is merely for convenience of description, and doesnot limit the scope of the present disclosure. Furthermore, some step(s)illustrated in FIG. 14 may be omitted depending on a situation and/or aconfiguration.

The UE may receive, from the BS, BFR related Config., that is,configuration information related to BFR and/or SR related Config., thatis, a configuration related to an SR (S1410). For example, theconfiguration information related to BFR may include configurationinformation related to an operation of Method 1/Method 1-1/Method1-2/Method 2/Method 3/Method 4 of Proposal 1. The configurationinformation related to BFR may include a resource configuration (e.g., aconfiguration for a BFR-PUCCH resource) for a BFR, configurationinformation for a timer or a counter. Furthermore, the configurationinformation related to an SR may include a resource configuration (e.g.,a configuration for an SR-PUCCH resource) for an SR, configurationinformation for a timer or a counter. The configuration informationrelated to BFR and/or the configuration information related to an SR maybe delivered through higher layer signaling (e.g., RRC signaling), etc.

For example, the operation of receiving, by the UE (100/200 in FIGS. 17to 21 ), the BFR related Config./SR related Config. from the BS in stepS1410 may be implemented by the apparatus of FIGS. 17 to 21 to bedescribed later. For example, referring to FIG. 18 , the one or moreprocessors 102 may control the one or more transceivers 106 and/or theone or more memories 104 to receive the BFR related Config./SR relatedConfig. The one or more transceivers 106 may receive the BFR relatedConfig./SR related Config. from the BS.

The UE may transmit a PUCCH (e.g., a BFR-PUCCH, a BFR related PUCCH, anSR-PUCCH, an SR related PUCCH) to the BS (S1420). For example, based onMethod 1/Method 1-1/Method 1-2/Method 2/Method 3/Method 4 of Proposal 1,the UE may transmit the PUCCH (e.g., a BFR-PUCCH, a BFR related PUCCH,an SR-PUCCH, an SR related PUCCH) to the BS. For example, when anSR-PUCCH resource and a BFR-PUCCH resource overlap, the UE maypreferentially transmit a BFRQ (i.e., a BFR-PUCCH) according to a givenrule, may transmit a BFRQ and an SR through separate PUCCH resources, ormay transmit BFR/SR-PUCCH based on separately defined/configured UCIbits, a sequence, or a sequence to which a cyclic shift (CS) has beenapplied according to a PUCCH format. Alternatively, the UE may notexpect a case where an SR-PUCCH resource and a BFR-PUCCH resourceoverlap itself. Furthermore, for example, prior to the PUCCHtransmission, an operation in the MAC layer described in Method 1/Method1-1/Method 1-2/Method 2/Method 3/Method 4 of Proposal 1 may bepreferentially performed. As a detailed example, in the case of a methodof preferentially transmitting, by the UE, a BFRQ, the operation in theMAC layer described in Table 15/Table 16 prior to the BFRQ transmissionmay be preferentially performed.

For example, the operation of transmitting, by the UE (100/200 in FIGS.17 to 21 ), the PUCCH to the BS in step S1420 may be implemented by theapparatus of FIGS. 17 to 21 to be described later. For example,referring to FIG. 18 , the one or more processors 102 may control theone or more transceivers 106 and/or the one or more memories 104 totransmit the PUCCH. The one or more transceivers 106 may transmit thePUCCH to the BS.

The UE may receive an UL grant (e.g., UL DCI) for PUSCH (e.g., aBFR-related PUSCH) scheduling from the BS (S1430). For example, withreference to Method 1/Method 1-1/Method 1-2/Method 2/Method 3/Method 4of Proposal 1, the PUSCH may be a PUSCH for delivering a MAC-CE (or UCI)including a corresponding beam RS ID (and/or quality (e.g., RSRP/SINR)of a corresponding beam) when a report (e.g., SCell(s) information(e.g., CC index(s)) in which a beam failure has occurred) related to BFRand/or whether a new beam for a corresponding SCell(s) is present and/ora new beam is present. That is, the UE may receive schedulinginformation of a PUSCH for delivering a MAC-CE (or UCI) including areport related to the BFR through a PDCCH (i.e., a PDCCH for an ULgrant).

For example, the operation of receiving, by the UE (100/200 in FIGS. 17to 21 ), the UL grant for PUSCH scheduling from the BS in step S1430 maybe implemented by the apparatus of FIGS. 17 to 21 to be described later.For example, referring to FIG. 18 , the one or more processors 102 maycontrol the one or more transceivers 106 and/or the one or more memories104 to receive the UL grant for PUSCH scheduling. The one or moretransceivers 106 may receive the UL grant for PUSCH scheduling from theBS.

The UE may transmit, to the BS, a PUSCH (e.g., a BFR-related PUSCH)scheduled based on the UL grant (S1440). For example, with reference toMethod 1/Method 1-1/Method 1-2/Method 2/Method 3/Method 4 of Proposal 1,the UE may transmit, to the BS, a MAC-CE (or UCI) including a beamreport including the BFR through the PUSCH.

For example, the operation of transmitting, by the UE (100/200 in FIGS.17 to 21 ), the PUSCH scheduled based on the UL grant to the BS in stepS1440 may be implemented by the apparatus of FIGS. 17 to 21 to bedescribed later. For example, referring to FIG. 18 , the one or moreprocessors 102 may control the one or more transceivers 106 and/or theone or more memories 104 to transmit the PUSCH scheduled based on an ULgrant. The one or more transceivers 106 may transmit the PUSCH scheduledbased on the UL grant to the BS.

As described above, the aforementioned BS/UE signaling and operation(e.g., Method 1/Method 1-1/Method 1-2/Method 2/Method 3/Method 4 ofProposal 1/FIG. 14 ) may be implemented by the apparatus (e.g., FIGS. 17to 21 ) to be described hereinafter. For example, the BS may correspondto a transmission apparatus/first apparatus, the UE may correspond to areception apparatus/second apparatus and an opposite case thereof mayalso be considered. For example, the aforementioned the BS/UE signalingand operation (e.g., Method 1/Method 1-1/Method 1-2/Method 2/Method3/Method 4 of Proposal 1/FIG. 14 ) may be processed by the one or moreprocessors (e.g., 102, 202) in FIG. 18 . The aforementioned BS/UEsignaling and operation (e.g., Method 1/Method 1-1/Method 1-2/Method2/Method 3/Method 4 of Proposal 1/FIG. 14 ) may be stored in a memory(e.g., the one or more memories 104, 204 in FIG. 18 ) in the form of aninstruction/program (e.g., an instruction or an executable code) fordriving the at least one processor (e.g., 102, 202) in FIG. 18 .

Hereinafter, the aforementioned embodiments are specifically describedwith reference to FIG. 15 from an operation aspect of a UE. Methodsdescribed hereinafter are classified merely for convenience ofdescription, and some elements of any one method may be substituted withsome elements of another method or they may be mutually combined andapplied.

FIG. 15 is a flowchart for describing a method of transmitting, by a UE,a physical uplink control channel in a wireless communication systemaccording to an embodiment of the present disclosure.

Referring to FIG. 15 , the method of transmitting, by a user equipment,a physical uplink control channel (PUCCH) in a wireless communicationsystem according to an embodiment of the present disclosure includessteps of receiving configuration information related to a PUCCH (S1510)and transmitting the PUCCH based on the configuration information(S1520).

In S1510, the UE receives, from abase station, configuration informationrelated to a physical uplink control channel (PUCCH). The configurationinformation related to the PUCCH may be based on at least one ofconfiguration information related to BFR or configuration informationrelated to an SR in FIG. 14 .

According to S1510, the operation of receiving, by the UE (100/200 inFIGS. 17 to 21 ), the configuration information related to the PUCCHfrom the base station (100/200 in FIGS. 17 to 21 ) may be implemented bythe apparatus of FIGS. 17 to 21 . For example, referring to FIG. 18 ,the one or more processors 102 may control the one or more transceivers106 and/or the one or more memories 104 to receive the configurationinformation related to the PUCCH from the base station 200.

In S1520, the UE transmits the PUCCH to the base station based on theconfiguration information.

According to an embodiment, the PUCCH may be transmitted in a PUCCHresource related to a scheduling request (SR).

Base on the PUCCH resource related to the SR being overlapped PUCCHresources, the PUCCH may be transmitted in a specific PUCCH resourcedetermined among the overlapped PUCCH resources.

The specific PUCCH resource may be related to beam failure recovery(BFR).

According to an embodiment, the beam failure recovery (BFR) may berelated to a beam failure of at least one secondary cell (SCell).

According to an embodiment, the specific PUCCH resource may be relatedto the PUCCH format 0 or the PUCCH format 1.

According to an embodiment, the PUCCH related to the beam failurerecovery (BFR) may be transmitted based on a parameter related to ascheduling request (SR). The parameter related to the scheduling request(SR) may be related to at least one of a timer related to thetransmission of the SR or a maximum transmission number of the SR Forexample, the timer related to the transmission of the SR may be based ona higher layer parameter sr-Prohi bitTimer. The maximum transmissionnumber of the SR may be based on a higher layer parameter sr-TransMax.

According to S1520, the operation of transmitting, by the UE (100/200 inFIGS. 17 to 21 ), the PUCCH to the base station (100/200 in FIGS. 17 to21 ) based on the configuration information may be implemented by theapparatus of FIGS. 17 to 21 . For example, referring to FIG. 18 , theone or more processors 102 may control the one or more transceivers 106and/or the one or more memories 104 to transmit the PUCCH to the basestation 200 based on the configuration information.

The method may further include a step of receiving downlink controlinformation (DCI). Specifically, in the step of receiving the DCI, theUE receives, from the base station, downlink control information (DCI)that schedules a physical uplink shared channel (PUSCH) related to thePUCCH. The present embodiment may be based on S1430 in FIG. 14 .

According to the step of receiving the DCI, the operation of receiving,by the UE (100/200 in FIGS. 17 to 21 ), the DCI that schedules the PUSCHrelated to the PUCCH from the base station (100/200 in FIGS. 17 to 21 )may be implemented by the apparatus of FIGS. 17 to 21 . For example,referring to FIG. 18 , the one or more processors 102 may control theone or more transceivers 106 and/or the one or more memories 104 toreceive, from the base station 200, the DCI that schedules the PUSCHrelated to the PUCCH.

The method may further include a step of transmitting a physical uplinkshared channel (PUSCH). Specifically, in the step of transmitting thePUSCH, the UE transmits the PUSCH to the base station based on the DCI.The present embodiment may be based on S1440 in FIG. 14 .

According to an embodiment, the PUSCH may be related to a medium accesscontrol-control element (MAC-CE) including information related to thebeam failure.

The MAC-CE may include information related to at least one of 1) atleast one secondary cell (SCell) or 2) a new beam.

The information related to a new beam may include at least one of i)whether the new beam is present or ii) an ID of a reference signalrelated to the new beam.

According to the step of transmitting the PUSCH, the operation oftransmitting, by the UE (100/200 in FIGS. 17 to 21 ), the PUSCH to thebase station (100/200 in FIGS. 17 to 21 ) based on the DCI may beimplemented by the apparatus of FIGS. 17 to 21 . For example, referringto FIG. 18 , the one or more processors 102 may control the one or moretransceivers 106 and/or the one or more memories 104 to transmit thePUSCH to the base station 200 based on the DCI.

Hereinafter, the aforementioned embodiments are specifically describedwith reference to FIG. 16 from an operation aspect of a base station.Methods described hereinafter are classified merely for convenience ofdescription, and some elements of any one method may be substituted withsome elements of another method or they may be mutually combined andapplied.

FIG. 16 is a flowchart for describing a method of receiving, by a basestation, a physical uplink control channel in a wireless communicationsystem according to another embodiment of the present disclosure.

Referring to FIG. 16 , the method of receiving, by the base station, thephysical uplink control channel in a wireless communication systemaccording to another embodiment of the present disclosure includes stepsof transmitting configuration information related to a PUCCH (S1610) andreceiving the PUCCH based on the configuration information (S1620).

In S1610, the base station transmits, to a UE, the configurationinformation related to the PUCCH. The configuration information relatedto the PUCCH may be based on at least one of the configurationinformation related to BFR or the configuration information related toan SR in FIG. 14 .

According to S1610, the operation of transmitting, by the base station(100/200 in FIGS. 17 to 21 ), the configuration information related tothe PUCCH to the UE (100/200 in FIGS. 17 to 21 ) may be implemented bythe apparatus of FIGS. 17 to 21 . For example, referring to FIG. 18 ,the one or more processors 202 may control the one or more transceivers206 and/or the one or more memories 204 to transmit, to the UE 100, theconfiguration information related to the PUCCH.

In S1620, the base station receives the PUCCH from the UE based on theconfiguration information.

According to an embodiment, the PUCCH may be transmitted in a PUCCHresource related to a scheduling request (SR).

Based on the PUCCH resource related to the SR being overlapped PUCCHresources, the PUCCH may be transmitted in a specific PUCCH resourcedetermined among the overlapped PUCCH resources.

The specific PUCCH resource may be related to beam failure recovery(BFR).

According to an embodiment, the beam failure recovery (BFR) may berelated to a beam failure of at least one secondary cell (SCell).

According to an embodiment, the specific PUCCH resource may be based onthe PUCCH format 0 or the PUCCH format 1.

According to an embodiment, the PUCCH related to the beam failurerecovery (BFR) may be transmitted based on a parameter related to thescheduling request (SR). The parameter related to the scheduling request(SR) may be related to at least one of a timer related to thetransmission of the SR or a maximum transmission number of the SR. Forexample, the timer related to the transmission of the SR may be based ona higher layer parameter sr-Prohi bitTimer, and the maximum transmissionnumber of the SR may be based on a higher layer parameter sr-TransMax.

According to S1620, the operation of receiving, by the base station(100/200 in FIGS. 17 to 21 ), the PUCCH from the UE (100/200 in FIGS. 17to 21 ) based on the configuration information may be implemented by theapparatus of FIGS. 17 to 21 . For example, referring to FIG. 18 , theone or more processors 202 may control the one or more transceivers 206and/or the one or more memories 204 to receive the PUCCH from the UE 100based on the configuration information.

The method may further include a step of transmitting downlink controlinformation (DCI). Specifically, in the step of transmitting the DCI,the base station transmits, to the UE, DCI that schedules a PUSCHrelated to a PUCCH. The present embodiment may be based on S1430 in FIG.14 .

According to the step of transmitting the DCI, the operation oftransmitting, by the base station (100/200 in FIGS. 17 to 21 ), the DCIthat schedules the PUSCH related to the PUCCH to the UE (100/200 inFIGS. 17 to 21 ) may be implemented by the apparatus of FIGS. 17 to 21 .For example, referring to FIG. 18 , the one or more processors 202 maycontrol the one or more transceivers 206 and/or the one or more memories204 to transmit, to the UE 100, the DCI that schedules the PUSCH relatedto the PUCCH.

The method may further include a step of receiving a physical uplinkshared channel (PUSCH). Specifically, in the step of receiving thePUSCH, the base station receives the PUSCH from the UE based on the DCI.The present embodiment may be based on S1440 in FIG. 14 .

According to an embodiment, the PUSCH may be related to a medium accesscontrol-control element (MAC-CE) including information related to thebeam failure.

The MAC-CE may include information related to at least one of 1) atleast one secondary cell (SCell) or 2) a new beam.

The information related to a new beam may include at least one of i)whether the new beam is present or ii) an ID of a reference signalrelated to the new beam.

According to the step of receiving the PUSCH, the operation ofreceiving, by the base station (100/200 in FIGS. 17 to 21 ), the PUSCHfrom the UE (100/200 in FIGS. 17 to 21 ) based on the DCI may beimplemented by the apparatus of FIGS. 17 to 21 . For example, referringto FIG. 18 , the one or more processors 202 may control the one or moretransceivers 206 and/or the one or more memories 204 to receive thePUSCH from the UE 100 based on the DCI.

Example of Communication System Applied to Present Disclosure

The various descriptions, functions, procedures, proposals, methods,and/or operational flowcharts of the present disclosure described inthis document may be applied to, without being limited to, a variety offields requiring wireless communication/connection (e.g., 5G) betweendevices.

Hereinafter, a description will be given in more detail with referenceto the drawings. In the following drawings/description, the samereference symbols may denote the same or corresponding hardware blocks,software blocks, or functional blocks unless described otherwise.

FIG. 17 illustrates a communication system 1 applied to the presentdisclosure.

Referring to FIG. 17 , a communication system 1 applied to the presentdisclosure includes wireless devices, Base Stations (BSs), and anetwork. Herein, the wireless devices represent devices performingcommunication using Radio Access Technology (RAT) (e.g., 5G New RAT(NR)) or Long-Term Evolution (LTE)) and may be referred to ascommunication/radio/5G devices. The wireless devices may include,without being limited to, a robot 100 a, vehicles 100 b-1 and 100 b-2,an eXtended Reality (XR) device 100 c, a hand-held device 100 d, a homeappliance 100 e, an Internet of Things (IoT) device 100 f, and anArtificial Intelligence (AI) device/server 400. For example, thevehicles may include a vehicle having a wireless communication function,an autonomous driving vehicle, and a vehicle capable of performingcommunication between vehicles. Herein, the vehicles may include anUnmanned Aerial Vehicle (UAV) (e.g., a drone). The XR device may includean Augmented Reality (AR)/Virtual Reality (VR)/Mixed Reality (MR) deviceand may be implemented in the form of a Head-Mounted Device (HMD), aHead-Up Display (HUD) mounted in a vehicle, a television, a smartphone,a computer, a wearable device, a home appliance device, a digitalsignage, a vehicle, a robot, etc. The hand-held device may include asmartphone, a smartpad, a wearable device (e.g., a smartwatch or asmartglasses), and a computer (e.g., a notebook). The home appliance mayinclude a TV, a refrigerator, and a washing machine. The IoT device mayinclude a sensor and a smartmeter. For example, the BSs and the networkmay be implemented as wireless devices and a specific wireless device200 a may operate as a BS/network node with respect to other wirelessdevices.

The wireless devices 100 a to 100 f may be connected to the network 300via the BSs 200. An AI technology may be applied to the wireless devices100 a to 100 f and the wireless devices 100 a to 100 f may be connectedto the AI server 400 via the network 300. The network 300 may beconfigured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g.,NR) network. Although the wireless devices 100 a to 100 f maycommunicate with each other through the BSs 200/network 300, thewireless devices 100 a to 100 f may perform direct communication (e.g.,sidelink communication) with each other without passing through theBSs/network. For example, the vehicles 100 b-1 and 100 b-2 may performdirect communication (e.g. Vehicle-to-Vehicle(V2V)/Vehicle-to-everything (V2X) communication). The IoT device (e.g.,a sensor) may perform direct communication with other IoT devices (e.g.,sensors) or other wireless devices 100 a to 100 f.

Wireless communication/connections 150 a, 150 b, or 150 c may beestablished between the wireless devices 100 a to 100 f/BS 200, or BS200/BS 200. Herein, the wireless communication/connections may beestablished through various RATs (e.g., 5G NR) such as uplink/downlinkcommunication 150 a, sidelink communication 150 b (or, D2Dcommunication), or inter BS communication (e.g. Relay, Integrated AccessBackhaul (IAB)). The wireless devices and the BSs/the wireless devicesmay transmit/receive radio signals to/from each other through thewireless communication/connections 150 a and 150 b. For example, thewireless communication/connections 150 a and 150 b may transmit/receivesignals through various physical channels. To this end, at least a partof various configuration information configuring processes, varioussignal processing processes (e.g., channel encoding/decoding,modulation/demodulation, and resource mapping/demapping), and resourceallocating processes, for transmitting/receiving radio signals, may beperformed based on the various proposals of the present disclosure.

Example of Wireless Device Applied to the Present Disclosure.

FIG. 18 illustrates wireless devices applicable to the presentdisclosure.

Referring to FIG. 18 , a first wireless device 100 and a second wirelessdevice 200 may transmit radio signals through a variety of RATs (e.g.,LTE and NR). Herein, {the first wireless device 100 and the secondwireless device 200} may correspond to {the wireless device 100 x andthe BS 200} and/or (the wireless device 100 x and the wireless device100 x) of FIG. 17 .

The first wireless device 100 may include one or more processors 102 andone or more memories 104 and additionally further include one or moretransceivers 106 and/or one or more antennas 108. The processor(s) 102may control the memory(s) 104 and/or the transceiver(s) 106 and may beconfigured to implement the descriptions, functions, procedures,proposals, methods, and/or operational flowcharts disclosed in thisdocument. For example, the processor(s) 102 may process informationwithin the memory(s) 104 to generate first information/signals and thentransmit radio signals including the first information/signals throughthe transceiver(s) 106. The processor(s) 102 may receive radio signalsincluding second information/signals through the transceiver 106 andthen store information obtained by processing the secondinformation/signals in the memory(s) 104. The memory(s) 104 may beconnected to the processor(s) 102 and may store a variety of informationrelated to operations of the processor(s) 102. For example, thememory(s) 104 may store software code including commands for performinga part or the entirety of processes controlled by the processor(s) 102or for performing the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document.Herein, the processor(s) 102 and the memory(s) 104 may be a part of acommunication modem/circuit/chip designed to implement RAT (e.g., LTE orNR). The transceiver(s) 106 may be connected to the processor(s) 102 andtransmit and/or receive radio signals through one or more antennas 108.Each of the transceiver(s) 106 may include a transmitter and/or areceiver. The transceiver(s) 106 may be interchangeably used with RadioFrequency (RF) unit(s). In the present disclosure, the wireless devicemay represent a communication modem/circuit/chip.

The second wireless device 200 may include one or more processors 202and one or more memories 204 and additionally further include one ormore transceivers 206 and/or one or more antennas 208. The processor(s)202 may control the memory(s) 204 and/or the transceiver(s) 206 and maybe configured to implement the descriptions, functions, procedures,proposals, methods, and/or operational flowcharts disclosed in thisdocument. For example, the processor(s) 202 may process informationwithin the memory(s) 204 to generate third information/signals and thentransmit radio signals including the third information/signals throughthe transceiver(s) 206. The processor(s) 202 may receive radio signalsincluding fourth information/signals through the transceiver(s) 106 andthen store information obtained by processing the fourthinformation/signals in the memory(s) 204. The memory(s) 204 may beconnected to the processor(s) 202 and may store a variety of informationrelated to operations of the processor(s) 202. For example, thememory(s) 204 may store software code including commands for performinga part or the entirety of processes controlled by the processor(s) 202or for performing the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document.Herein, the processor(s) 202 and the memory(s) 204 may be a part of acommunication modem/circuit/chip designed to implement RAT (e.g., LTE orNR). The transceiver(s) 206 may be connected to the processor(s) 202 andtransmit and/or receive radio signals through one or more antennas 208.Each of the transceiver(s) 206 may include a transmitter and/or areceiver. The transceiver(s) 206 may be interchangeably used with RFunit(s). In the present disclosure, the wireless device may represent acommunication modem/circuit/chip.

Hereinafter, hardware elements of the wireless devices 100 and 200 willbe described more specifically. One or more protocol layers may beimplemented by, without being limited to, one or more processors 102 and202. For example, the one or more processors 102 and 202 may implementone or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP,RRC, and SDAP). The one or more processors 102 and 202 may generate oneor more Protocol Data Units (PDUs) and/or one or more Service Data Unit(SDUs) according to the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document. Theone or more processors 102 and 202 may generate messages, controlinformation, data, or information according to the descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document. The one or more processors 102 and 202 maygenerate signals (e.g., baseband signals) including PDUs, SDUs,messages, control information, data, or information according to thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document and provide thegenerated signals to the one or more transceivers 106 and 206. The oneor more processors 102 and 202 may receive the signals (e.g., basebandsignals) from the one or more transceivers 106 and 206 and acquire thePDUs, SDUs, messages, control information, data, or informationaccording to the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document.

The one or more processors 102 and 202 may be referred to ascontrollers, microcontrollers, microprocessors, or microcomputers. Theone or more processors 102 and 202 may be implemented by hardware,firmware, software, or a combination thereof. As an example, one or moreApplication Specific Integrated Circuits (ASICs), one or more DigitalSignal Processors (DSPs), one or more Digital Signal Processing Devices(DSPDs), one or more Programmable Logic Devices (PLDs), or one or moreField Programmable Gate Arrays (FPGAs) may be included in the one ormore processors 102 and 202. The descriptions, functions, procedures,proposals, methods, and/or operational flowcharts disclosed in thisdocument may be implemented using firmware or software and the firmwareor software may be configured to include the modules, procedures, orfunctions. Firmware or software configured to perform the descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document may be included in the one or more processors102 and 202 or stored in the one or more memories 104 and 204 so as tobe driven by the one or more processors 102 and 202. The descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document may be implemented using firmware or softwarein the form of code, commands, and/or a set of commands.

The one or more memories 104 and 204 may be connected to the one or moreprocessors 102 and 202 and store various types of data, signals,messages, information, programs, code, instructions, and/or commands.The one or more memories 104 and 204 may be configured by Read-OnlyMemories (ROMs), Random Access Memories (RAMs), Electrically ErasableProgrammable Read-Only Memories (EPROMs), flash memories, hard drives,registers, cash memories, computer-readable storage media, and/orcombinations thereof. The one or more memories 104 and 204 may belocated at the interior and/or exterior of the one or more processors102 and 202. The one or more memories 104 and 204 may be connected tothe one or more processors 102 and 202 through various technologies suchas wired or wireless connection.

The one or more transceivers 106 and 206 may transmit user data, controlinformation, and/or radio signals/channels, mentioned in the methodsand/or operational flowcharts of this document, to one or more otherdevices. The one or more transceivers 106 and 206 may receive user data,control information, and/or radio signals/channels, mentioned in thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document, from one or moreother devices. For example, the one or more transceivers 106 and 206 maybe connected to the one or more processors 102 and 202 and transmit andreceive radio signals. For example, the one or more processors 102 and202 may perform control so that the one or more transceivers 106 and 206may transmit user data, control information, or radio signals to one ormore other devices. The one or more processors 102 and 202 may performcontrol so that the one or more transceivers 106 and 206 may receiveuser data, control information, or radio signals from one or more otherdevices. The one or more transceivers 106 and 206 may be connected tothe one or more antennas 108 and 208 and the one or more transceivers106 and 206 may be configured to transmit and receive user data, controlinformation, and/or radio signals/channels, mentioned in thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document, through the one ormore antennas 108 and 208. In this document, the one or more antennasmay be a plurality of physical antennas or a plurality of logicalantennas (e.g., antenna ports). The one or more transceivers 106 and 206may convert received radio signals/channels etc. From RF band signalsinto baseband signals in order to process received user data, controlinformation, radio signals/channels, etc. using the one or moreprocessors 102 and 202. The one or more transceivers 106 and 206 mayconvert the user data, control information, radio signals/channels, etc.Processed using the one or more processors 102 and 202 from the baseband signals into the RF band signals. To this end, the one or moretransceivers 106 and 206 may include (analog) oscillators and/orfilters.

Example of Signal Processing Circuit Applied to the Present Disclosure

FIG. 19 illustrates a signal process circuit for a transmission signal.

Referring to FIG. 19 , a signal processing circuit 1000 may includescramblers 1010, modulators 1020, a layer mapper 1030, a precoder 1040,resource mappers 1050, and signal generators 1060. An operation/functionof FIG. 19 may be performed, without being limited to, the processors102 and 202 and/or the transceivers 106 and 206 of FIG. 18 . Hardwareelements of FIG. 19 may be implemented by the processors 102 and 202and/or the transceivers 106 and 206 of FIG. 18 . For example, blocks1010 to 1060 may be implemented by the processors 102 and 202 of FIG. 18. Alternatively, the blocks 1010 to 1050 may be implemented by theprocessors 102 and 202 of FIG. 18 and the block 1060 may be implementedby the transceivers 106 and 206 of FIG. 18 .

Codewords may be converted into radio signals via the signal processingcircuit 1000 of FIG. 19 . Herein, the codewords are encoded bitsequences of information blocks. The information blocks may includetransport blocks (e.g., a UL-SCH transport block, a DL-SCH transportblock). The radio signals may be transmitted through various physicalchannels (e.g., a PUSCH and a PDSCH).

Specifically, the codewords may be converted into scrambled bitsequences by the scramblers 1010. Scramble sequences used for scramblingmay be generated based on an initialization value, and theinitialization value may include ID information of a wireless device.The scrambled bit sequences may be modulated to modulation symbolsequences by the modulators 1020. A modulation scheme may includepi/2-Binary Phase Shift Keying (pi/2-BPSK), m-Phase Shift Keying(m-PSK), and m-Quadrature Amplitude Modulation (m-QAM). Complexmodulation symbol sequences may be mapped to one or more transportlayers by the layer mapper 1030. Modulation symbols of each transportlayer may be mapped (precoded) to corresponding antenna port(s) by theprecoder 1040. Outputs z of the precoder 1040 may be obtained bymultiplying outputs y of the layer mapper 1030 by an N*M precodingmatrix W. Herein, N is the number of antenna ports and M is the numberof transport layers. The precoder 1040 may perform precoding afterperforming transform precoding (e.g., DFT) for complex modulationsymbols. Alternatively, the precoder 1040 may perform precoding withoutperforming transform precoding.

The resource mappers 1050 may map modulation symbols of each antennaport to time-frequency resources. The time-frequency resources mayinclude a plurality of symbols (e.g., a CP-OFDMA symbols and DFT-s-OFDMAsymbols) in the time domain and a plurality of subcarriers in thefrequency domain. The signal generators 1060 may generate radio signalsfrom the mapped modulation symbols and the generated radio signals maybe transmitted to other devices through each antenna. For this purpose,the signal generators 1060 may include Inverse Fast Fourier Transform(IFFT) modules, Cyclic Prefix (CP) inserters, Digital-to-AnalogConverters (DACs), and frequency up-converters.

Signal processing procedures for a signal received in the wirelessdevice may be configured in a reverse manner of the signal processingprocedures 1010 to 1060 of FIG. 19 . For example, the wireless devices(e.g., 100 and 200 of FIG. 18 ) may receive radio signals from theexterior through the antenna ports/transceivers. The received radiosignals may be converted into baseband signals through signal restorers.To this end, the signal restorers may include frequency downlinkconverters, Analog-to-Digital Converters (ADCs), CP remover, and FastFourier Transform (FFT) modules. Next, the baseband signals may berestored to codewords through a resource demapping procedure, apostcoding procedure, a demodulation processor, and a descramblingprocedure. The codewords may be restored to original information blocksthrough decoding. Therefore, a signal processing circuit (notillustrated) for a reception signal may include signal restorers,resource demappers, a postcoder, demodulators, descramblers, anddecoders.

Example of Application of Wireless Device Applied to the PresentDisclosure

FIG. 20 illustrates another example of a wireless device applied to thepresent disclosure.

The wireless device may be implemented in various forms according to ause-case/service (refer to FIG. 17 ). Referring to FIG. 20 , wirelessdevices 100 and 200 may correspond to the wireless devices 100 and 200of FIG. 18 and may be configured by various elements, components,units/portions, and/or modules. For example, each of the wirelessdevices 100 and 200 may include a communication unit 110, a control unit120, a memory unit 130, and additional components 140. The communicationunit may include a communication circuit 112 and transceiver(s) 114. Forexample, the communication circuit 112 may include the one or moreprocessors 102 and 202 and/or the one or more memories 104 and 204 ofFIG. 18 . For example, the transceiver(s) 114 may include the one ormore transceivers 106 and 206 and/or the one or more antennas 108 and208 of FIG. 18 . The control unit 120 is electrically connected to thecommunication unit 110, the memory 130, and the additional components140 and controls overall operation of the wireless devices. For example,the control unit 120 may control an electric/mechanical operation of thewireless device based on programs/code/commands/information stored inthe memory unit 130. The control unit 120 may transmit the informationstored in the memory unit 130 to the exterior (e.g., other communicationdevices) via the communication unit 110 through a wireless/wiredinterface or store, in the memory unit 130, information received throughthe wireless/wired interface from the exterior (e.g., othercommunication devices) via the communication unit 110.

The additional components 140 may be variously configured according totypes of wireless devices. For example, the additional components 140may include at least one of a power unit/battery, input/output (I/O)unit, a driving unit, and a computing unit. The wireless device may beimplemented in the form of, without being limited to, the robot (100 aof FIG. 17 ), the vehicles (100 b-1 and 100 b-2 of FIG. 17 ), the XRdevice (100 c of FIG. 17 ), the hand-held device (100 d of FIG. 17 ),the home appliance (100 e of FIG. 17 ), the IoT device (100 f of FIG. 17), a digital broadcast terminal, a hologram device, a public safetydevice, an MTC device, a medicine device, a fintech device (or a financedevice), a security device, a climate/environment device, the AIserver/device (400 of FIG. 17 ), the BSs (200 of FIG. 17 ), a networknode, etc. The wireless device may be used in a mobile or fixed placeaccording to a use-example/service.

In FIG. 20 , the entirety of the various elements, components,units/portions, and/or modules in the wireless devices 100 and 200 maybe connected to each other through a wired interface or at least a partthereof may be wirelessly connected through the communication unit 110.For example, in each of the wireless devices 100 and 200, the controlunit 120 and the communication unit 110 may be connected by wire and thecontrol unit 120 and first units (e.g., 130 and 140) may be wirelesslyconnected through the communication unit 110. Each element, component,unit/portion, and/or module within the wireless devices 100 and 200 mayfurther include one or more elements. For example, the control unit 120may be configured by a set of one or more processors. As an example, thecontrol unit 120 may be configured by a set of a communication controlprocessor, an application processor, an Electronic Control Unit (ECU), agraphical processing unit, and a memory control processor. As anotherexample, the memory 130 may be configured by a Random Access Memory(RAM), a Dynamic RAM (DRAM), a Read Only Memory (ROM)), a flash memory,a volatile memory, a non-volatile memory, and/or a combination thereof.

Example of Hand-Held Device Applied to the Present Disclosure

FIG. 21 illustrates a hand-held device applied to the presentdisclosure. The hand-held device may include a smartphone, a smartpad, awearable device (e.g., a smartwatch or a smartglasses), or a portablecomputer (e.g., a notebook). The hand-held device may be referred to asa mobile station (MS), a user terminal (UT), a Mobile Subscriber Station(MSS), a Subscriber Station (SS), an Advanced Mobile Station (AMS), or aWireless Terminal (WT).

Referring to FIG. 21 , a hand-held device 100 may include an antennaunit 108, a communication unit 110, a control unit 120, a memory unit130, a power supply unit 140 a, an interface unit 140 b, and an I/O unit140 c. The antenna unit 108 may be configured as a part of thecommunication unit 110. Blocks 110 to 130/140 a to 140 c correspond tothe blocks 110 to 130/140 of FIG. 20 , respectively.

The communication unit 110 may transmit and receive signals (e.g., dataand control signals) to and from other wireless devices or BSs. Thecontrol unit 120 may perform various operations by controllingconstituent elements of the hand-held device 100. The control unit 120may include an Application Processor (AP). The memory unit 130 may storedata/parameters/programs/code/commands needed to drive the hand-helddevice 100. The memory unit 130 may store input/output data/information.The power supply unit 140 a may supply power to the hand-held device 100and include a wired/wireless charging circuit, a battery, etc. Theinterface unit 140 b may support connection of the hand-held device 100to other external devices. The interface unit 140 b may include variousports (e.g., an audio I/O port and a video I/O port) for connection withexternal devices. The I/O unit 140 c may input or output videoinformation/signals, audio information/signals, data, and/or informationinput by a user. The I/O unit 140 c may include a camera, a microphone,a user input unit, a display unit 140 d, a speaker, and/or a hapticmodule.

As an example, in the case of data communication, the I/O unit 140 c mayacquire information/signals (e.g., touch, text, voice, images, or video)input by a user and the acquired information/signals may be stored inthe memory unit 130. The communication unit 110 may convert theinformation/signals stored in the memory into radio signals and transmitthe converted radio signals to other wireless devices directly or to aBS. The communication unit 110 may receive radio signals from otherwireless devices or the BS and then restore the received radio signalsinto original information/signals. The restored information/signals maybe stored in the memory unit 130 and may be output as various types(e.g., text, voice, images, video, or haptic) through the I/O unit 140c.

Effects of the method and apparatus for transmitting and receivingphysical uplink control channels in a wireless communication systemaccording to an embodiment of the present disclosure are described asfollows.

According to an embodiment of the present disclosure, a physical uplinkcontrol channel (PUCCH) is transmitted in a PUCCH resource related to ascheduling request (SR). Based on the PUCCH resource related to the SRbeing overlapped PUCCH resources, the PUCCH is transmitted in a specificPUCCH resource determined among the overlapped PUCCH resources. Thespecific PUCCH resource is related to beam failure recovery (BFR).

Beam failure recovery may be performed based on a PUCCH related to ascheduling request. The beam failure recovery (BFR) can also beeffectively supported for a secondary cell (SCell). In particular, whena beam failure occurs in a secondary cell (SCell) for a high frequencyband (e.g., 30 GHz), beam failure recovery can be more effectivelyperformed.

Furthermore, when a PUCCH resource related to beam failure recoveryoverlaps a PUCCH resource related to a scheduling request (e.g., an SRattributable to an event other than beam failure recovery), a PUCCHresource related to the beam failure recovery may be transmitted to havepriority. Accordingly, when an SR event and a BFR event simultaneouslyoccur, ambiguity in a UE operation can be solved, and a beam failurerecovery procedure (BFR procedure) can be more quickly initiated.

If a UE notifies a base station of only the occurrence of a beam failurethrough a PUCCH, relatively small information (e.g., 1 bit) isdelivered. In this aspect, the PUCCH needs to be transmitted using theexisting procedure.

According to an embodiment of the present disclosure, a PUCCH related tobeam failure recovery (BFR) is transmitted based on a parameter relatedto the scheduling request (SR). The parameter related to the schedulingrequest (SR) is related to at least one of a timer related to thetransmission of the SR or a maximum transmission number of the SR.Accordingly, the beam failure recovery (BFR) can be initiated based onthe existing scheduling request procedure.

If a base station is notified of only the occurrence of a beam failure,a subsequent report related to beam failure recovery needs to beperformed. According to an embodiment of the present disclosure, a UEreceives downlink control information (DCI) that schedules a PUSCHrelated to a PUCCH, and transmits the PUSCH based on the DCI. The PUSCHis related to a medium access control-control element (MAC-CE) includinginformation related to the beam failure. The MAC-CE includes informationrelated to at least one of 1) at least one secondary cell (SCell) or 2)a new beam. Accordingly, detailed information related to a beam failurecan be effectively delivered through a PUSCH scheduled based on theexisting scheduling procedure.

The embodiments of the present disclosure described above arecombinations of elements and features of the present disclosure. Theelements or features may be considered selective unless otherwisementioned. Each element or feature may be practiced without beingcombined with other elements or features. Further, an embodiment of thepresent disclosure may be constructed by combining parts of the elementsand/or features. Operation orders described in embodiments of thepresent disclosure may be rearranged. Some constructions of any oneembodiment may be included in another embodiment and may be replacedwith corresponding constructions of another embodiment. It is obvious tothose skilled in the art that claims that are not explicitly cited ineach other in the appended claims may be presented in combination as anembodiment of the present disclosure or included as a new claim bysubsequent amendment after the application is filed.

The embodiments of the present disclosure may be achieved by variousmeans, for example, hardware, firmware, software, or a combinationthereof. In a hardware configuration, the methods according to theembodiments of the present disclosure may be achieved by one or moreApplication Specific Integrated Circuits (ASICs), Digital SignalProcessors (DSPs), Digital Signal Processing Devices (DSPDs),Programmable Logic Devices (PLDs), Field Programmable Gate Arrays(FPGAs), processors, controllers, microcontrollers, microprocessors,etc.

In a firmware or software configuration, the embodiments of the presentdisclosure may be implemented in the form of a module, a procedure, afunction, etc. For example, software code may be stored in a memory unitand executed by a processor. The memories may be located at the interioror exterior of the processors and may transmit data to and receive datafrom the processors via various known means.

Those skilled in the art will appreciate that the present disclosure maybe carried out in other specific ways than those set forth hereinwithout departing from the spirit and essential characteristics of thepresent disclosure. The above embodiments are therefore to be construedin all aspects as illustrative and not restrictive. The scope of thedisclosure should be determined by the appended claims and their legalequivalents, not by the above description, and all changes coming withinthe meaning and equivalency range of the appended claims are intended tobe embraced therein.

The invention claimed is:
 1. A method performed by a user equipment in awireless communication system, the method comprising: receivingconfiguration information related to a Scheduling Request (SR); andtransmitting the SR on a valid Physical Uplink Control Channel (PUCCH)resource among PUCCH resources based on the configuration information,wherein the valid PUCCH resource is based on a PUCCH resource on abandwidth part (BWP) which is active at a time of SR transmissionoccasion, and wherein, based on one or more PUCCH resources overlappingwith a PUCCH resource for a Secondary Cell (SCell) beam failure recoveryfor the SR transmission occasion: the PUCCH resource for the SCell beamfailure recovery among the overlapping PUCCH resources is determined asvalid, and the SR is transmitted on the PUCCH resource for the SCellbeam failure recovery.
 2. The method of claim 1, wherein the PUCCHresource for the SCell beam failure recovery is based on a PUCCH format0 or a PUCCH format
 1. 3. The method of claim 1, further comprisingreceiving downlink control information (DCI) scheduling a physicaluplink shared channel (PUSCH) related to the SR.
 4. The method of claim3, further comprising transmitting the PUSCH based on the DCI.
 5. Themethod of claim 4, wherein the PUSCH is related to a medium accesscontrol-control element (MAC-CE) including information related to thebeam failure recovery (BFR).
 6. The method of claim 5, wherein theMAC-CE includes information for at least one of 1) an index related toat least one SCell in which a beam failure is detected or 2) a new beam.7. The method of claim 6, wherein the information for the new beamincludes i) whether the new beam is present and ii) an ID of a ReferenceSignal (RS) related to the new beam.
 8. The method of claim 1, whereinthe transmission of the SR is performed based on i) a timer related tothe transmission of the SR and ii) a maximum transmission number of theSR.
 9. A user equipment configured to operate in a wirelesscommunication system, the user equipment comprising: one or moretransceivers; one or more processors; and one or more memoriesoperatively coupled to the one or more processors and storinginstructions that, based on being executed by the one or moreprocessors, perform operations comprising: receiving, through the one ormore transceivers, configuration information related to a SchedulingRequest (SR); and transmitting, through the one or more transceivers,the SR on a valid Physical Uplink Control Channel (PUCCH) resource amongPUCCH resources based on the configuration information, wherein thevalid PUCCH resource is based on a PUCCH resource on a bandwidth part(BWP) which is active at a time of SR transmission occasion, andwherein, based on one or more PUCCH resources overlapping with a PUCCHresource for a Secondary Cell (SCell) beam failure recovery for the SRtransmission occasion: the PUCCH resource for the SCell beam failurerecovery among the overlapping PUCCH resources is determined as valid,and the SR is transmitted on the PUCCH resource for the SCell beamfailure recovery.
 10. A base station configured to operate in a wirelesscommunication system, the base station comprising: one or moretransceivers; one or more processors; and one or more memoriesoperatively coupled to the one or more processors and storinginstructions that, based on being executed by the one or moreprocessors, perform operations comprising: transmitting, through the oneor more transceivers, configuration information related to a SchedulingRequest (SR), and receiving, through the one or more transceivers, theSR on a valid Physical Uplink Control Channel (PUCCH) resource amongPUCCH resources based on the configuration information, wherein thevalid PUCCH resource is based on a PUCCH resource on a bandwidth part(BWP) which is active at a time of SR transmission occasion, wherein,based on one or more PUCCH resources overlapping with a PUCCH resourcefor a Secondary Cell (SCell) beam failure recovery for the SRtransmission occasion: the PUCCH resource for the SCell beam failurerecovery among the overlapping PUCCH resources is determined as valid,and the SR is received on the PUCCH resource for the SCell beam failurerecovery.